DavidTheWinsaamLKincheloeHalftime was an ESEA construct so they didn't need to totally rewrite their plugins for TF2, IIRC.
That being said, removing halftime is a way of taking 5-10 empty minutes out of a match and use it for playtime.
Especially in TF2 I think half time is really important, otherwise turtling is way too good. Go up 2 rounds with like 15 minutes left, cap 4th and run an engie, game is basically over. Even if you don't go that hard, you can still easily kill time on mid or 4th as long as you want and force the other team to push out. Halftime gives a team a couple minutes to talk strats and forces another mid fight.
Even if you want to lessen it to 20 minute halves with windifference 5 I think halftime is really important.
If that strategy was even remotely effective you'd see it all the time in ETF2L and in reality it pretty much never happens. You might see the bus being parked with 2 minutes left if you're 1 round up say but you'd see that in ESEA too. You also get 5-10 minutes between maps to discuss things with your team. The 2 map ETF2L system is pretty much the same as the ESEA half system except it's on a different map and the two halves are scored independently.
This thread isn't about the pros/cons of either format, if you want that discussion it should be raised elsewhere.
My opinion is to use the ETF2L ruleset (or a variant) as that is what the majority of the world is familiar with, even North Americans through the i-series events and I think CEVO also ran it?
I think it's because no team cares enough to take 8 minutes to push last. That doesn't make it not a problem.