So, what's new? Silicon designers have been baking specific functions into silicon forever, in pursuit of better performance. For example, one didn't need an 8087 maths coprocessor to do maths but it's a lot faster with one.
The real problems come when "custom" gets used to lock up a market, create monopolies. If an AWS customer gets hooked on some bespoke Amazon AI accelerator they can't use market competition to get a fair price.
The only good thing about what's going on is that with all these vendors putting so much effort into making it easy for customers to build ideas into product, it becomes easier to reimplement that product from scratch on some other hosting platform offering similar capabilities. Hopefully the hosting platform providers will overdo what they provide and make this too easy. It then becomes normal to develop your cloud app for, say, AWS and get it working there, and then redo it on Azure, Google, whomever, and keep those in one's back pocket. If AWS becomes too expensive, fire up the Azure version of your cloud app, shift the data over, bye bye Bezos.
That's basically what happened with cars. By deskilling driving, suddenly there's no reason to be brand loyal. Cloud app development is not yet at that level, but by trying to make it "easy*, they're headed that way.
My fear is that they'll realise this, and work against that in subtle ways, eg by making it expensive to bulk export one's data, or being shit at DNS cache cleaning, or something like that. For example Google, running their own DNS servers, could "accidentally" make your life hell if you'd had the cheek to move your website off their servers to Amazon's. "That's a nice web address you have got there, want it to continue to resolve properly to your AWS microservices?".
With a lot of these providers also being active in the search and advertising market too, the opportunities for them to suppress competition in Cloud are immense. Google are well known for exploiting their search muscle to force companies to advertise with them. Unrestrained, they and the others will do the same with hosting and AI.
"Advertise with us, like your competitor does, and maybe you'll get an AI as smart as the one they're running. No? Oh dear, your AI has just lost a few neurons, got a bit thick as it were, senility is such a sad thing to see in a machine as wonderful as yours... ".