Yeah, I doubt it is as heated as Revan. That's about as controversial as it gets.
But I feel that this particular topic is a very interesting one because it (unlike other topics) isn't dictated by canon. We don't know for SURE what would have happened if the Jedi had entered the war, and this means that there is room for opinions. There is no absolute right or absolute wrong, and that makes this topic interesting.
That's true. We don't know what would have happened. But like Rayla said, the Emperor would have come in eventually.
The way I see it, there are many different ways the war could have gone down.
1. What did happen
2. The Jedi don't join the war at all
3. The Jedi join the war when things get really bad
4. The Jedi join the war right away
Option 1 led to the Jedi Civil War. Option 2 would lead to the Republic being destroyed. Option 3 would lead to the Jedi Civil War and the Republic being destroyed. Option 4 leads to the Jedi Civil War and the Republic being destroyed. But the outcome doesn't matter as the Emperor would have attacked eventually. What matters about these outcomes is who
the Emperor would fight.
Option 1 is what we have now in TOR. Option 2 the Emperor takes control from Mandalore, with or without conflict. Option 3 and 4 the Emperor fights the "Sith" and the Star Forge.
EDIT: But these are only a few outcomes and paths that could have been taken.