But there isn't really an option for that. You basically choose between either running a sub yourself or simply not having the sub. There's no actual choice to get paid to run a sub.
At closest, you can create a community on a site you own, but then you don't get the advantage of all those Reddit users, the easy hosting that works even if your sub scales to millions of people, or the tools that are provided or created by others specifically for Reddit.
Even here on the Fediverse, there isn't really an option to get paid and there's still no guarantee that your hard work won't get destroyed (unless you put in a bunch of extra work and the expense to use your own instance, too). Ads are basically impossible unless you control the instance that people register in (it doesn't matter if the community is hosted on a different instance). Donations are basically the only option.