This. 100 times this. Also, in several places most of the services downtimes are due to, you know what? Application bugs, not infrastructure outages. Sure, they happen as well and being on a good cloud provider mitigate a lot of them (but not all of them!) but if you increase the application design complexity you will increase also those downtimes. Yeah sure, there are tens of really good engineering departments where everything is properly CI?CD, automated, they can scale to thousand of services without skipping a beat... but that's not the reality for thousands of other smaller/less talented shops. So, "moving to serverless" will not just automagically fix all of your problems.

Also - and I'm an infra guy so I'm probably biased - I don't really get all this developer anxiety to outsource infra needs. Yeah if you are 2 devs working on your startup it makes sense, but when you scale up the team/company, even with serverless, you WILL need to dedicate time to infra/operations and do not dedicate it to strictly-business-related code. Having somebody dedicated to this is good for both.