Another tattoo disagreement in a marriage

Turns out this is a pretty common marital issue now and I get to experience it.

On our first date, I brought up tattoos and body modification with my now spouse. I do not find this attractive in any way and I wanted to be upfront about my preference. My SO said they didn't have either and didn't want them, so I proceeded with the relationship.

Fourteen years later, SO is about to turn 40 and mentioned wanting to get a small tattoo on the inside of a finger that would match what other family members have. I fully grant this would be a subtle and discreet single tattoo, though I frankly think one would become multiple because that's how it seems to be when people get inked.

I said it's their body and they an do with it what they choose. I reminded that this was a strong enough preference for me that I mentioned it on the first date and that I could not guarantee what my reaction would be aside from it not being positive.

What I did not say to avoid appearing controlling is I think I would find my SO somewhat disgusting with any tattoo, no matter how subtle. I also don't believe it would end with one and multiple tattoos and/or non subtle ones would 100% lead to a divorce. If I see a tattoo during intimacy, that session would be over and I sure as hell don't want to think about in-laws during sex.

Not looking for advice because my SO might never get one and if it did happen, I'll make my own decision. I would like to hear from people whose spouses changed and decided to make a change that thry knew their SO strongly disliked.