A12 was in the XR, XS/XS MAX u nonce

Yes, I am disappointed with Apple once more for not including certain phones in their updates...I bought an iPhone 8 two years ago as I was coming from an iPhone SE model.

Now it seems, if I am to benefit from all that Apple offers, I need to sell my phone and invest in a newer model to be up to date with all that Apple would have us believe we desire.

They do not actually play a fair game with their old customers and sooner or later those old customers will go elsewhere.
So much for looking after your potential past customers.

A11 has a very weak neural engine which explains a lot (0,6 TOPS for A11 vs 5+ TOPS for A12 and newer). Live captions not working on the Xs (A12, 2658mAh) is because it has a much smaller battery than the 11 Pro (A13, 3046mAh) since it works on A12 powered iPads. It also helps with milking iPhone buyers so win-win?
But I hate that Apple decides which features come to which device instead of users choosing themselves. I'd bet a lot of Xs users would be happy to have live caption even though it would drain their battery which only happens because Apple put a tiny cell in.