Grindr etiquette

Hey, what do you tell a guy when they share their face pic and you realize that you're not attracted to him? I find ghosting/blocking to be highly insulting, but wouldn't saying "I'm not attracted to you" also be insulting?Is there a polite and proper way to end a conversation with a guy without hurting his feelings? (This matters to me because my biggest complaint about gay men is how vain we are, and apps like Grindr only seem to glorify this vanity. I want to be a considerate user but I'm not sure what to say, hence me reaching out to y'all for advice.)Thank you