I worry about it too. What I have found is that it's important to keep your skills very, very current. It's OK to be reasonably skeptical about the latest hotness, but it's imperative to know about it and why it's the latest hotness. No one cares (OK very few people care) about the systems you built in perl in the 90's. They will care about your opinion Go vs. Rust vs. C++, even if you are not an expert in any of them. You needn't have used every no-SQL data store, but again you need to know about them.
On the other hand if you are a subject matter expert in a particular domain, then your twenty years of experience are indeed very useful, and while no one wants to replicate the risk reporting system you built in Motif/X in the 90's, they may well want build it in React.
On the other hand if you are a subject matter expert in a particular domain, then your twenty years of experience are indeed very useful, and while no one wants to replicate the risk reporting system you built in Motif/X in the 90's, they may well want build it in React.