Fishing pressure on a lake is controlled by the number of parking spaces at the ramp. If the ramp only allows 30 boats, the most that will be on the water is 30 boats regardless of hp restriction or not.

As for me, I have a 40hp. however that doesn't stop me from fishing hp restricted lakes like, Banner, Evergreen, Sangchris, etc. My batteries will last all day, however it takes forever to get anywhere. With the 40, I can also fish bigger bodies of water, like Clinton, Shelbyville, Canadian shield lakes, etc. I won't fish Clinton or Shelbyville in the summer months due to pleasure boaters, they don't care about fishing and chew the crap out of the water. With "no wake" at the smaller lakes, I can fish in peace, even with a 40hp traveling 5mph. Sure it's only 1.5mph faster than my TM, but it won't take all day to get anywhere. Plus running the big motor recharges my sonar, live-well, cranking battery so I can get off the water at the end of the day. I'm good with the change.