In CSGO MM, people can troll the way they want, like buying pistols only, dropping the C4 in a dangerous place, whole team buying sniper rifles etc. But, at least in decent rankings, people rarely do those things because they don't want to lose their ranks.
It will be the same in TF2, in the lower ranks there will be a lot of laughable shit going on, like it happens in Silver matches in CSGO, because there will be a lot of people who have 0 experience with competitive playing, but at decent ranks people will play to win so those kind of things will become rare, even rarer than in TF2 Center because there you have nothing to lose.