The point is, you build a shack so you can build a cathedral where it’s warranted. If you are stuck maintaining a cathedral you can’t move on to bigger better things.

Yep, you build a shack and charge the users the price of a starbucks latte per month because "it's just a starbucks latte".

Then you wonder why the solo founder saas has no customers.

I'm not sure what you're talking about; but what I was trying to say is I tend to see teams get charged with building X (which should be a cathedral), but then build a cathedral of configuration parsing, and a cathedral of CRUD; instead of focusing on X.