Midi thrus actually work, but you are creating a daisy chain, so when you need to add something, or worse, remove a device it’s a lot of work, but MIDI devices like the old 8X8s I still have in my rack have a major advantage the mean you don’t have to fix the MIDI channels in the DAW. If you have a thru daisy chain, then your DAW and the keyboards/samplers etc all have to be set to new channels, so the piano on 1, the synth on 2 and so on. getting it wrong makes multiple devices respond. The patch bay means you leave them all on their default channel, and just tell the DAW to send to each device separately. Much more friendly. The M audio ones I have were excellent devices.
