Oh the options get way better than that. Check these guys out: https://accessanalog.com
They have 60+ rack units with little robot grabbers physically controlling the knobs.
Re analogue summing, yeah it does near nothing in reality. What you're missing though is that what people actually want with analogue summing isn't really technically better sound but technically worse sound. Analogue gear might have a little bit of harmonic distortion, a little bit of crosstalk between channels, certain transformer characteristics etc that theoretically make it sound more glued together or warm etc etc. But ultimately summing is summing and those differences vs. digital are very small (and won't always contribute positively either).