to stand up to game theory. If there are ways to manipulate or rig the system to an outcome which suits an attackers goals, then it's no good. We can't inadvertently introduce that kind of weakness.
Friendly fire! Friendly fire!, lol. Are we still talking about future upgrades here? Because despite my lack of understanding about the entirety of taproot, I am pretty much certain that what you just described is happening right now, I swear I'm not lying or trolling, you can check to see those orange blocks turning to red and are about to explode on mempool.space.
Fair point. Even when it seems like every reasonable precaution has been taken, there can still be unforseen consequences. Clearly no one saw this current situation coming. Part of the concept behind Taproot was to assist with scaling, signature aggregation, etc. But someone found a way to exploit it to create a way to upload crap and molest mempools. Every advancement leads us into unexplored territory, but it's still worth taking every reasonable precaution. Even if there are no guarantees someone won't immediately look for a way to abuse the change.