[scarface74]

Once a well-meaning developer introduces local application state

And this would break the minute you have more than one web server. How many websites of any consequence are running on only one web server?

Having server side session state that can be shared across servers is a solved problem as is having a load balancer that handles “sticky sessions”. I’m not saying either is a good idea.

Also if you are “locking your database” even if you use a faster runtime, you’re just delaying the inevitable of your scaling limits.