Earlier quoted context omitted.
>If the barriers to entry are too high, then price controls or nationalization. Or remove the barriers, like regulation/licensing/taxation.
The barrier is capital expenditure, not regulation/licensing/taxation. Besides, any competitor entering the market would be expected to make just as much or more profit as the existing companies. Which means they would price their product just the same as the existing companies.
I don't think you can just decide by fiat that things like regulation and licensing aren't barriers. Taxi medallions before Uber comes to mind.
>Besides, any competitor entering the market would be expected to make just as much or more profit as the existing companies
You also cannot just decide by fiat that adding more competitors mean the same amount or more profit. I don't think it is a very popular economic opinion to believe that adding more competition raises the profit. I do not understand why any rational competitor would expect their profit would be higher with more competition, unless they have some kind of edge.