Pretty much this. I know lot of people hate Linkedin but the fact is that if you are a job candidate and have little to no Linkedin, it's a huge potential red flag in today's world. Lot of scammers, overemployeds/moonlighters out there.

When I was moonlighting LinkedIn didn’t affect me. Every time I applied/interviewed and got hired for a w2 job, I just left my last non moonlighting employer on there, and checked the “please don’t contact current employer” checkbox. I hadn’t worked there in over a year.

Didn’t my new employer want me to update my LinkedIn? That never came up, but if it would have I would have delayed. Why should I support their business model.

Especially if someone has 25 years of experience as the OP said.