Advantage of erx/eds is not only the price, but customization. You can set number of gears, you can set up each gear individually. If, for some reason, you want to change cassette from 12 speed to 10 or 11, or vice versa, you just unscrew old components, install new, and do a few clicks in the app to tune your gear. With big brands you need to buy a new shifters and derailleurs.
So if erx/eds will be reliable as shimano/sram, and cost the same as 105/rival, it still be a good choice.