That's why I prefer to invest time and effort on AWS. I know I won't have to rewrite everything from scratch whenever Google feels like abandoning their projects.
To the best of my knowledge, no. At least none of the AWS services I've used. They've deprecated support for some CAs and stuff, but that seems reasonable.
There have been rare changes, like mandatory API version upgrades or some features being turned off. I do not recall anything being removed without a (better) replacement available beforehand, let alone entire simply services being turned off. See simpleDB as the canonical example of long term deprecation but continued availability.
Disclosure: long time Principal at AWS. The above is my own observation and opinion
Not that I'm aware of. They'd be fully justified in shutting down simpleDB since it hasn't had a feature update in over a decade, but they still keep it running. New accounts can't sign up for it and it only exists in the oldest regions.
They were going to retire old s3 path styles, but they changed their mind after customer feedback.
That's exactly what you will do - invest time, and energy, a lot of both because AWS is a victim of its own legacy. Everything is an after-thought, everything is messy and its genuinely painful to use on anything except some basic UI driven functionality.
EC2 and S3 and some basic hosting stuff is fine but newer services such as AWS Glue, Athena etc are a horrendous mess for anything other than 101 type stuff.
EC2-Classic was not its own service. It was a specific configuration of EC2. They retired that configuration by providing a full migration path into a new system that could be configured to perfectly replicate the old system if you wanted it to. Having gone through that migration myself with a bunch of services a long time ago, this isn't really a good example of a thing that AWS has killed off.
Not trolling, seriously asking (I don't use hyperscalers)