How much do you need to learn though? Why not settle for .Net or Java or Node or Django or Rails (if doing web)? They didn't change that brutally in the past 10

How much do you need to learn though? Why not settle for .Net or Java or Node or Django or Rails (if doing web)? They didn't change that brutally in the past 10 years. Sure, there are changes, but nothing that 2-4 hours of catching up monthly won't fix. I think the issue becomes worse when you change stacks a lot, that isn't very sustainable to me.