I don't know if I would call them unanswered punches and it's a bit of a tricky matter to judge the intelligent defense criteria here. Cruz wasn't blocking the punches, but he was most certainly trying to improve his position and to some degree he accepted being punched (to another he was of course rocked). Certainly a fair stoppage, but given how much he worked to change his position the people that wanted it to go longer aren't without merit either.
the only problem here is that it all happened really quickly.
he got dropped, was trying to get back up - only to be dropped again, and then hit a bunch of a times from turtle, all in a matter of seconds.
he may have been trying to improve position, but it didn't look like it right up to the point that the ref stepped in. the ref waved it off at pretty much the same time dominick managed to pop back up, which is unfortunate, but the ref can't really be faulted for it. he's looking at the twice knocked down fighter taking shots in turtle.
with our benefit of hindsight, we all know cruz could have gone on longer. but at the time, from the refs perspective? the guy was seriously hurt, on all fours, with his face turned towards the mat, taking shots. facing the mat in the turtle position is not intelligent defense, no matter how often we actually see it in fights.
think of it this way. had cejudo landed the exact same amount of punches, and cruz didn't get up as the ref stopped it, but instead stayed on his knees, no one would be protesting the stoppage. so the only thing that changed the optics for us at the time was the fact that cruz got up the same split second.
i can understand dominick's frustration, but trying to blame the ref by saying he smelled like booze is just a bitch move. it's entirely impossible to verify and it smears the guy's reputation, the only way he can defend himself is by lashing back out at dominick, which he did, and now they both look like assholes.