When I'm interested in someone they know
Also to the OP sorry I made some assumptions, but from what I know of myself and maybe other ISTPs is that friends are primarily people we do activities with or talk face to face with
Not to say the texting couldn't work but could he have been putting that extra effort in because he was interested at some point?
The alternative scenario that he only ever wanted friendship I call BS on with the making out, unless you were just completely coming on to him and thought it was going both ways but wasn't
After some thinking about this my conclusion is that he isn't interested romantically and thinks that friendship wont work (for what reason I am unsure)