>>717888143 (OP)
Not a hero shooter. No ults other than medic and possibly spy cloak.
Mostly mutually exclusive gameplay between classes. Medics are indisputably the best at healing, soldiers are the best at aoe, demo are the best at non line of sight, scout is the best at being fast, sniper is the best at long range, heavy is the best at DPS with no mitigation, spy goes invis, engineers build bases, and pyro is the best at close range.
Yes, class expertise bleeds into one another, but the overall paradigm of each character is distinct, and even their design is meant to invoke impressions that reinforce this.
Contrast this to overwatch where the classes are divided into DPS tank and support, with 20 characters in each category, no shit tf2 is going to feel memorable.