I generally work for small companies, and while I'll do something very similar when taking leave (or just at the weekend) I do also make sure someone has contact details for me in the case of anything that truly can't wait until I get back. My experience of doing this has been that people will be judicious about whether something actually warrants interrupting someone's holiday, and it also results in me being less inclined to check in on email/Slack now and again just in case something is up.

I was the only full time sysadmin of a 20 person company. I went on vacation for three whole weeks. I was half way around the globe and not reachable. The company still existed after I came back. They did have a problem. They tried to reach me. They couldn't. They figured it out by themselves.

I think we believe ourselves to be more irreplaceable than we are. And if you really think you are irreplaceable then the problem is not going on vacation but being irreplaceable. Because then if something were to happen to you they are screwed.