I have a GoPro 8 and use the
official waterproof housing to protect the camera. The case does a good job of protecting the lens and body from dents and scratches. I set up the camera before the trip and then only have to switch it on when I want to record video or change to take a picture. So I only need to use the buttons and not the touch screen.
You can also use an open back panel on the case, which would allow use of the touchscreen and I think better sound recording, but I prefer more protection and only need to use the buttons.
I've just replaced my case as one of the two plastic legs for attachments cracked, but it hadn't yet fallen off as the other one was still ok. I managed to get a new one cheaper through Amazon Warehouse (must have been a return as packaging unopened). I had the original case for almost 4 years and it has held up well.
A cheaper option may be the
Rollecage which has hard plastic for the lens but silicone body. This case uses the metal legs of the camera itself so would be more robust then the case plastic ones. Though this case would still protect the lens, the silicone body gives less protection from bangs so you may end up with dents!
If you happen to have a GoPro 8 the official website has a sale on for the waterproof case £33 rather than £55, and Rollcage £18 rather than £30. Though it says £12 delivery so perhaps not such a great deal unless you are looking to pick up some other bits and hit the threshold for free delivery. Amazon has the rollecage for £25.
They used to offer free GoPro subscription for a few months when you purchased a new camera, I used this to buy my original case for half price.
At the end of the day a waterproof case is much cheaper than having to buy a new camera!