One person's rich services are another's vendor lock-in.

If you're referring to AWS's "serverless" offering, they are mostly managed instances of FLOSS offerings with the exception of dynamodb, and arguably are far from justifying the colossal premium they charge for using them. I mean, does anyone claim with a straight face that without AWS it's practically impossible to get a database or a message broker up and running?

It’s a completely different thing to „get it up and running” and to fully operate and monitor 24/7 a highly available environment using full time SREs with strict contracted SLAs.

Your comment is rather disingenuois and naive. If you have any experience whatsoever with AWS you wouldbe fully aware that AWS quite vocally advertises that reliability is the responsibility of the customer,not theirs. Theygo even further by stating in their "well-architected framework" that it's on you to handle redundancy with multiple deployments across separate availability zones. So your baseless assertions fly in the face of reason once you actually lay attention to the operational side, because as it's easy to see and understand it makes absolutely no difference if you parrot keywords all day because in the end reliability is on you, and if it's up to you anyway then that is not an argument in favour of vendor lock-in.