If you came away from the sabbatical refreshed and ready for new things that alone would be worthwhile.
Rich Hickey's creative sabbatical gave us Clojure:
"I started working on Clojure in 2005, during a sabbatical I funded out of retirement savings. The purpose of the sabbatical was to give myself the opportunity to work on whatever I found interesting, without regard to outcome, commercial viability or the opinions of others. One might say these are prerequisites for working on Lisps or functional languages. I budgeted for two years of self-directed work, and Clojure was one of two projects I pursued. After about a year I decided the other project (a cochlear modeling and machine listening problem) was more of a research endeavor that might require two to five more years, so I dedicated myself at that point to getting Clojure to a useful state."
Source: https://download.clojure.org/papers/clojure-hopl-iv-final.pd...
As long as you have the savings to do it, I say go for it.