That is not true, at least in Age of Empires 2 which is the RTS I'm most familiar. Have a look at the limited viper series to see a good player destroy using only 60 APM. If you make good decisions, you don't need to click as much.

https://www.youtube.com/watch?v=s7moDQK1Yng&list=PLrFe08sgKX493Gax5DFNkpEbgICGDc0YJ

Why can’t you just set a standing order of “make unit x” or “make unit x while we have gas until we get to 50 of them”?

Because while this will make casuals that will play the game for 3 hours and drop it happy, the typical RTS fans will not enjoy this. There is a trade off between queuing a lot of units and having more resources available for other techs. Having units auto produce without any disadvantage is just kind of boring. Then you are just watching the game, not really playing it.

Maybe you should try turn based strategy, if you don't like real time strategy. In the later, like the name implies, time is the most important resource. You don't need a lot of clicks, but you need to use it wisely.