> Literally no one benefits from the alternative.
Future you might disagree with present you. But even if we disregard time, I think millions of consumers would benefit from the opportunity to have competitive markets again. If an actual economic forest fire was allowed to burn, we might eliminate some of the too-big-to-fail corruption and oligopoly that is the norm now and provide space for new seeds to grow.
You can’t have competition forever. At some point someone wins decisively, and then there is only the illusion of competition.
The problem with this idea which is common in some circles is that most of the businesses involved are commodity or lowish margin. They likely got built either with government support or before the current margin's were a thing. Becdause you can't make a high enough ROI on building a new competitor your seeds will likely die in barren soil never having germinated. In today's markets the likely result will be increased business going to China, India, Vietnam and the like. If you're talking about banking then the worst possible scenario at a national level is that you're borrowing money denominated in a foreign currency. The adventure after 1929 was a result of deliberate policy to liquidate and let it burn.