Besides their very dubious product strategy which consists of shipping the org chart, which with the apparently high turnover results in multiple competing but basically abandoned product lines..
There's the security issues. If their AWS infra for their cloud services is that shit (as was revealed by a hack by an internal person), i doubt security is taken seriously in the org in general. Not to mention them suing security reporters.
Unlike their sometimes dubious hardware QA, it doesn't impact you that much if you plan on flashing your own firmware on their hardware, but still, those are kind of turnoffs. Hardware quality seems to vary somewhat, but is mostly decent.
but they're determined to run their company into a wall chasing people who want dumb guis instead of their basically abandoned uniquely awesome edgerouter series that isnt really matched in terms of consumer performance.
What does it matter what they do with their OS ? That's their OS to ruin. Making a crap OS is the rite of passage for every hardware vendor. The whole reason for running openwrt is to replace the vendor's OS. As long as they don't lock bootloaders, hardware is judged based on upstream support, and ER-X is perfectly fine.