It is relevant, it's a totally appropriate response to the GP comment. Snapchat hasn't been primarily a nude-sharing app for a long time, and the fact that some people seem to go out of their way to remain ignorant about that and keep treating it as such is the exact kind of intentional smug ignorance that the "ok boomer" meme is mocking.
I understand, but my reply was meant to allude to both how out of touch the older generation is and also how they look down at snapchat. I have snapchat and I use it everyday pretty much, its so much more than just sending nudes, so it irks me a bit when someone calls it just a nude sharing app. Thus my reply.
But I am a millennial who literally uses Snap for this very purpose and pretty much only this purpose - like most of the people I know who use it. Otherwise, it’s WhatsApp.