Everything has been tried on bikes more than once already. Why is no one seriously looking at hydraulic systems?
Indeed, but sometimes an idea has to wait for technologies to catch up. I’m sure somebody tried a hydro disc brake on a bike ages ago and decided that, on balance, it was lumpen pain-in-the-ar$e. Fast forward to a time of CNC machines, market demand, ecomonies of scale and better/more available material (amoungst a, probably, long list) and Bob’s-your-mothers-brother.
Doesn’t mean I think it’s a good/bad idea just that its time isn’t now (for all of the reasons discussed above, and Di2 in particular)…. as it may, or may never, be in the future.