I might be a bit biased since I’m mostly on blu,I might even change my opinion later idk,but now I wanna share my own experience here as a blu.
In most maps,the cell areas are actually pretty small. Unless the warden is Obi wan and takes the high ground it takes less than 1 sec for scouts to rush up and deal 2 melee hits while other takes like at most 2 seconds to kill a blu. And at maps with super small cell areas (Ahem volcano) it wouldn’t even take even more than half a second. Lets not forget close corners,small blu side mini games like some in alakatra or hidden ammo spots (which are mostly likely the time they would rebel)takes less than half a second for someone to rush the warden while he’s distracted. The average human reaction speed is about 0.25 seconds so we already spent half the time trying to react with 0.25 seconds left.Now normally it already takes more than half a second to switch to your melee(since most people prefer to have their gun out most of the time). Unless you’re using a shotgun(Quick tip,only 2 out of 9 have) or a rocket launcher,you’ll be the rest 6/9 classes and would prefer taking out his melee and most likely be hit once unless you’re a scout or if tf2 melee is being itself,which already puts you in an disadvantage.
You would say “what about blu guarantee crits”? Well,let’s continue the situation. Now you’ve been hit once due to the delay in reaction time and weapon switch speed. Lets be optimistic and pretend the first hit isn’t a crit,and unless you’re super lucky,the next hit would have a huge chance for being a random crit? Both of you are in an even ground,with a 50/50 chance it seems pretty good right? However let’s not forget how the tf2 melee works,when you get attacked,you would backtrac as a normal reaction since walking forward means you’re walking towards the red group,which is a bad thing. Now let’s not forget in tf2 melee,the one walking forward will automatically have an advantage for having a longer melee range. So the warden,with guarantee crits,is acrually having a disadvantage when a red faces him due to random crits. Moreover if 1 rebels,it is likely that 1-2 would follow up,so now you’re 45% or even 40% chance of surviving turned into a 20% chance. Welp,good luck on winning that because I guarantee you the blus won’t stick to you 24/7 because they need to watch the other reds.(Or worse,if you’re a blu nobody would help if you’re getting rushed)Oh you didn’t clutch a 1v2 where you only have a 20% chance of winning? Such an incompetent blu
(Don’t forget the worst situation where you don’t even have a chance to fight back because the first hit is a random)
TLDR: Gurantee crits does not give blus an advantage but instead because of random crits+reaction time+how tf2 melee works+number advantage of reds,gives you an disadvantage. And most of the time getting face to face melee fight with a red is unavoidable unless you’re an inactive warden