For me it is more about not leaving all the comfort zones all at once. Say if I start doing a project with 5 different technologies in the stack, I pick at least 4 that I’m solid with and maybe 1 wildcard.

E.g. I got interested SvelteJS exactly because I got jaded of how ridiculously complex many front end applications have gotten, albeit they are doing just barely more than fetching a JSON from a server and turning it into html. Then I got a really good use case for using it in production because the low end mobile phones and bad internet connections of our users were struggling with the very heavy SPA the company started off with.

For another project in the future, it might well be SQLite that is the more experimental part, but in the end it comes down to managing risks and benefits.

While one part of me would love to experiment with everything all the time, the other part likes to finish the work day on time to be able to have plenty time dedicated to non tech related things and that sleeps well at night being fairly sure that stuff is running smoothly

Very reasonable approach, I like it.