its more than a shame. emoji, gifs and images are a core part of teens' communications (I have one, I know all too well), and iMessage's green bubble is also a guarantee that these things won't work, so its not just a shame, it is a hard road block.
Based on all the messages I get from my work colleagues (mostly android users much more into memes and things than I am), gifs and emojis and other features work just fine these days with MMS messaging on iPhone.
When iMessage has to send a pic or vid to a group that contains non-iMessage recipients, iMessage will fallback to MMS and may need to recompress the pic/vid to get under the MMS media limit.
MMS, introduced in 2002, has much lower limits for pictures/video than if the messaging apps were to send the media over data/internet.
Also these MMS media limits aren't hardcoded, the limits are set by the sending and receiving carriers.
videos taken on your or their phones don't show up postage stamp sized and blurry/bricky any more? that's usually how a green bubble drags an iphone group down
although the "liked your message" type stuff is also annoying.
Fortunately a lot of teens moved to discord.