We already know lowering the cut doesn't make us pay less. All it does is put more money into the pockets of the publisher.
And I very much doubt Valve's cut is a reason indie game can't be profitable. There are asset flips going up on Steam on a daily basis. If asset flipping wasn't profitable we wouldn't see them propping up like mushrooms after rain. When asset flips are more profitable than an indie game there's something wrong with that game.
That applies to games people know about. If nobody knows about your game then it doesn't count. For example Vampire survivors barely made any money on the first few weeks of its early access release. In fact it didn't really start making money until youtubers/streamers essentially advertised it for free.