I don't bother with "mesh" type setups specifically, but yeah, router/switch in one device (usually with one or more additional switches for more ports and/or newer wired standards) and APs in separate devices with ethernet backhaul.
These APs could still be all-in-one routers if they have good wifi hardware/drivers and have OpenWrt support, but they are treated as dumb APs that could be swapped in/out if problems occur.