AWS is pretty far from dominating these days. Ms in particular has eaten up a lot of the cloud marketshare. It is huge but definitely not the overwhelming share that they used to have.
Most people using AWS literally can't switch because most people work for someone else...I don't think corporate really gives a shit if I don't like the cloud platform we use
That mentality only works in the "adopting cloud" stage. Vendor lock-in is real, and AWS was doing what it does long before there even were competitors, let alone ones with feature parity.
If you start a job somewhere of any reasonable size with incumbent AWS infrastructure, switching to another provider will be an uphill struggle in the best possible circumstance and in most cases it will be a Sisyphean exercise that'll probably end up with you out of a job before the AWS bill goes down
I have a voice in my role, but I'm not going to pretend I'm the only person at the company.
I'm more making the point that your single voice will not be sufficient to affect direction regarding cloud provider choice in a big enough company, that dice was probably already rolled a decade ago. I'm not saying it's impossible or anything, but you're gonna need to come up with an incredible business case for throwing away years of hundreds of engineers' work building on top of platform A for a costly switch to platform B all for no customer benefit.
I mean, vendor lock-in and lack of resiliency to a vendor-specific outage, maybe caused by some piece of their stack you have never nor will ever touch, or maybe the platform CEO decides your kind of company isn't expedient for their business anymore, are among the reasons why a company should never have ended up in that situation in the first place.
You can continue along that road of least resistance while ignoring all of the risks. That is up to you. You'll probably be fine. (Not joking, you'll be fine. But don't pretend like this is all necessary.)