It's your bosses job to make sure there aren't single points of failures. If you try hard to become one, they might start trying hard to make you not one. You'r

It's your bosses job to make sure there aren't single points of failures. If you try hard to become one, they might start trying hard to make you not one. You're now a bottleneck, after all. Some places have toxic cultures so that's the norm, but if you're fortunate to be at a better place, don't force their hand to go down that route! (There's also the aspect where if you're the only person who can do X, but now someone needs to do Y which will actually be ten times more valuable to the company than X, you've closed off that opportunity for yourself!)