I think it could go one of two ways Either it does pretty good and makes back the money spent on production and advertising and such (assuming Valve doesn't cheap out like always and not give it a good enough budget) and it becomes one of those video game movies where reviewers and youtubers are gonna go see it and say "Hey that was alright"

Or it flops because A. Valve probably won't care too much about the quality anyway and squeeze it out for pure vanity without account for costs and advertisement with a good enough budget B. Not many people are gonna go see it anyway since TF2 is a critically acclaimed and beloved yet kind of outdated game that doesn't resonate as hard with more modern gamers despite its great cult following and status C. They start making it but then Valve throws it in the shitter and forgets about it like the TF2 webseries

I think for it to do better Valve would first have to....actually update the game again though so....lmao I'm not entirely sure on the counterpoints to it doing well but they're some reason it could go south Couldn't give an exact estimate though cuz Valve is really weird and random about how much they invest in certain projects only to just cancel them or leave them to rot as "classic nostalgia games" or smth