That's the problem with the community. I would love to see an hybrid system, keeping the functionalities of the forums while having a voting system that highlights the "hottest" comments in a thread based in votes and timeframe.
If there's a will, ad hominem can be moderated. It's WAY MORE LIKELY that someone who is high ranked UNDERSTANDS the game that someone who is low ranked. This is not SC2 or CS:GO where you need high levels of physical input in order to perform well.
The same points you bring now has been brought in the past. This "fear" of hurting people's ego and gatekeeping is why you don't have quality discussions been done. You need some kind of filter so you have a more selected discussion been done while keeping it public so people can see. At the same time you give the space in the same forum but another sub section so everyone can discuss freely.
Well we have already seen top player that even play in tournaments lack basic knowledge of the game mechanics because basically you do not need to know the mechanics of how things work and know the end result is enough.