In my view, and as someone who's never used instant messaging, it should be a small accommodation to make for a friendship. In the same way that I would be happy to provide a vegetarian option at a dinner.
Few people understand "this messenger is slightly less privacy focused. It's owned by Meta. It's against my principles".
I am vegan so I would definitely break ties with friends that make mean "jokes" about veganism or myself. But I certainly would never let go of friends because they want me to use WhatsApp.
Similarly, I live sans messaging for the simple reason that I never upgraded to a smartphone. In the 2000s this solicited reactions of amazed befuddlement and surprise, occasionally mirth. Nowadays, in my experience, most people intuitively understand the decision.
Demanding all your friends switch or kill their messaging apps is quite another matter, and an eccentric one at that.
Then, from A's perspective, it is just a small accommodation for B to communicate through alternative means. And from B's perspective, it is just a small accommodation for A to use $APP.
"Look, I am not letting Zuck suck up my personal data and watch ads if there is an alternative that's owned by a non-profit, does not show ads and end-to-end encrypts everything as a rule."
Asking to use Zucks apps anyway as a small accommodation would paint the one asking as an ignorant who is being unreasonable and does not take care of their digital hygiene properly. Sure, they might resent the other person for pointing their own failings out, but it's hard to actually argue.
Within their value system, they're not being ignorant. Rather, they're perfectly rational.
There is an incentive to converge to $APP, the tradeoffs are not collectively symmetric when one $APP is already globally dominant.