A normal conversation at normal volume is normal.

Loud and obnoxious is not normal. We all know what those conversations sound like on a plane. They annoy everyone. If that was the case, then the OP has me in his corner.

OP: Simple answer is the best. Use Headphones or earplugs. AND . . . coming on to FT an asking people what you should do and what is appropriate always gets these sorts of response . . . generally snarky and unsympathetic.

Don't ask strangers on an internet board what to do . . . do what you think is correct.

In your case, you did nothing, that bothered you, then grumbled about it on FT.