I went private to utility back to private.
Utility has its perks. Stable, decent pay, good benefits, generally easy work (no weird specs, clear goals).
The wrong private site companies would be doing worse off than utilities, so you'd want to be cautious in your switch.
Some skills transfer well, some don't. Private side generally requires more rope skills, rigging skills, people skills, and a way different tool bag of pruning skills (objective based).
Utility work can be political and full of red tape. It is gaining more clout these days, and even has its own climbing comps. I was union out of Washington State, and the trimmers from that local were really good dudes. It was a good place to work.
It's not that either one is better or worse. It depends on your situation, risk tolerance life wise, mentality towards work, and local companies that you could jump ship and work for (there's more than just wages from your prospective company). There's less regulation on private side, so more shitty companies.
If you've got more specific questions feel free to give me a shout. Hell we're hiring a journeyman, I'd make it worth your while. Lol.