Total mikrotik noob here...

Current setup:
Edgerouter POE -> Mikrotik CSR125-RM -> Ubiquiti UAP-AC-Pro + other devices

I needed a lot of ports, but frankly don't care at all about managed features right now (bought the Mikrotik for future proofing).

So... is the default config equivalent to an unmanaged switch? The touchscreen interface is kind of wonky and hard to use, so I can plug in for CLI.

By default CRS125 is configured as a simple switch.

Configuring master-port setting enables switching on CRS