The problem is that up until 2005, everything mostly fit and made sense, or was explained later. Odd changes like the Trill makeup and the Romulan forehead were rare, and minor compared to what Disco changed. The Kelvin timeline allowed more drastic changes without affecting prime continuity. So what makes Disco so frustrating is that we've enjoyed pretty well maintained consistency until recently, and then suddenly (with a new creative team) we got drastic changes that don't fit anymore. If the makers had been that careless for the previous 50 years already, it wouldn't have mattered, but it's sad to see something you're a fan of lose its standards after such a long time.