The rubber wheel metros are mostly a result of lobbying by Michelin. They're an interesting curiosity, but I think there is a reason why they haven't really caught on outside of France...
The Paris Metro lines using rubber tires are almost all retrofitted (line 1, 4, 6 and 11, only line 14 was operated with rubber tired trains from the start).
Retrofitting actually has some advantages for old lines with short station distances, tight curves and steep gradients, whereas new lines can be planned with the limitations of rail technology in mind.
The Chinese have nearly doubled the metros built in both number and mileage in the last two decades. And pretty much none of those are rubber tired either.
Rubber tired metros are also a niche in new metros.
The East Asian economic miracles are all heavily export dependent. Part of the pillar of this industrial strategy is to heavily support emerging technologies, because they can then gain economies of scale, first mover knowledge, etc. This has happened before, with technologies like plasma screens, LCDs and LEDs, and is now happening in China with solar panels and electric cars. They have developed such advanced manufacturing capabilities so quickly and are now almost insurmountable market leaders, or at least major competitors.
Railways are also part of this strategy. China, Japan and Korea all export railway products from high speed rail to subways to monorails, and so in this context rubber tired metros are another niche technology to get an edge in. Note that this strategy doesn't always work; no one outside of these countries is very interested in maglev trains, for example.
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The other part of this is development finance. Countries that do not have know-how with big infrastructure projects often look to international institutions to build projects and secure financing. And part of the deal is that if you take French money you must spend it on French suppliers, and this is true for basically any country doing this kind of lending, so basically the lender is getting both interest payments and spending towards its economy. The Chinese and Japanese compete a lot for railway projects in particular; Japan built the Taiwanese HSR and the Hanoi and Ho Chi Minh City metros, China is currently building high speed rail in Thailand and Laos, etc.
Those benefits have eroded a bit over time. Rail vehicles have become pretty good at acceleration and deceleration, with acceleration often being limited due to passenger comfort.
Similarly high(er) grades of 8%-10% are now quite possible with high-performing vehicles.
8-10% Woah: Where? Tokyo's Toei Oedo (circle) line is considered steep by modern standards and has special cars with "linear induction motors" that can traverse up to 5% grade.
Wikipedia claims reason for the linear motor on the Oedo line was a smaller loading gauge and therefore smaller tunnels required.
And generally speaking 5 % wouldn't be considered very steep at all by modern standards. Gradients up to 4 or even 5 % weren't uncommon even on older rapid transit systems dating from a century ago, and for modern multiple units I'd regard 4 to 6 % as about par for the course.
And in hilly terrain, a number of systems definitively go beyond that into the 8 – 10 % range, including some new built systems (e.g. the light rail systems in Stuttgart, Tenerife and Jerusalem).
One (or more?) of Paris metro lines is rubber wheel, the one up to la defense, rubber is simply better at climbing hills. The ouchy line in Lausanne is also rubber for the same reason (since it climbs from lake geneva up and up).
Unless you go with a rack railroad, or maybe a cable way, you are only climbing hills with rubber.
So they say indeed! Interesting! I have lived there long enough and didn't notice. They are all pretty quiet. To be fair, it's possible to run on rubber and still mess it up, noise-wise, like BART does with gusto.
To follow up on my previous comment: BART is a master class in institutional incompetence, the Peter Principle in action if you will. So, yes, BART uses steel track and wheels with a steel outer surface but they've still managed to fuck it up ten ways from Sunday.
The article you linked to talks about all the money that BART's thrown at the noise problem without addressing the elephant(s) in the room: BART cars are aluminum tubes that are inherently noisy and BART wears its tracks aggressively. The first iterations had carpeted floors which absorbed some of the noise, but those got predictably gross.
Much of the track noise comes from corrugation because the wheels are dragged over the track. Other systems might grease their wheels so that there's more slip in turns, BART can't. Other systems sand the tracks in wet weather so you don't skid, BART can't. Modern systems have anti-skid systems so that you don't wear the wheels. Bombardier's anti-skid system is awful. So the new cars flat spot the wheels at a much higher rate than the old and you get noisy track (and noisy trains as they thump thump thump down the track). BART grind the rails and the noise goes away for a bit, but it eventually comes back with a vengeance because they're doing everything they can to avoid addressing the underlying problems.
They’re fine. They make for less noise, less vibration, and better acceleration. They might be more expensive to maintain and less common, but there is nothing archaic about them.
One interesting correlation I found is that the rubber tyre metro’s also have platform doors, and the steel wheel metro’s dont have doors on the platforms.
Not really. AFAIK there are platform doors on lines 1, 4, 14 and 13.
Lines 1, 4 and 14 have rubber tyres and platform doors because they are fully automated (or in the case of line 4 in the process of being fully automated). So far Paris only fully automates rubber tyres lines.
Line 13 has classic metal tyres and is only semi-automated, but it has platform doors because it is very high traffic. Most Parisians avoid line 13 at rush hours because it is probably the most packed line in the city.
