the best argument for rpi has always been the combination of GPIO and linux. But that's a double-edged sword too, because linux isn't really very good at hard-realtime. And you can always just get a Bus Pirate or similar tool for doing just plain GPIO. And nowadays the ESP32 has basically completely displaced it for a lot of those sorts of "GPIO glue" roles.
If you didn't need that, like if you just wanted a low-power fileserver or HTPC... the x86 stuff was better, because it actually worked reliably, at roughly the same price. Like literally just go buy an off-lease mini-tower or USFF mini-pc for $10 from a surplus store, even.
This goes doubly when you consider all the problems with the early rpi. Like basically it uses USB 2.0 (unidirectional 500mbps) as a system bus... but it also dropped USB packets under load due to bugs in the firmware[0], that nobody outside the Pi foundation could address because Broadcom didn't release the documentation for like 5 years.