Maybe it's because I've been on Windows for too long, but people are always complaining about how terrible Windows 10 (and soon to be 11 is) as an experience (See recent slowdown with AMD processors). That and a little bit too much time watching all the cool things people did with 1mhz processors with no L1 cache or graphics, on 80s computers. As someone who wasn't around during that time, it's easy to get the feeling that a 1.5ghz quad core cpus +.5ghz gpu should absolutely slay any program, but in my experience using the RPI4 as a primary computer it hasn't felt that way.

> For software that was written in a performance insensitive way (i.e. not games) you perhaps could achieve a 100 times performance increase by a full rewrite avoiding various overheads. However, you would not really need an OS change for that, the main performance-relevant changes would be in the app itself and you can get almost all of that by running the optimized app on a standard OS - but you would need a rewrite of all the actual software.

I think this is insightful. I agree that not everything would be 100x, but I feel like at the level of an RPI 4 even a 5-10% improvement that bumps a game into 30 or 60fps territory would be noticeable. And even a 2x improvement in regular apps would have impact.