Yeah, though in the UK's case, that would have been by choice, rather than because their entry had been repeatedly vetoed.

Also, related trivia for those not familiar (despite the fact that it's been the source of a whole lot of noise due to Brexit), the UK and Ireland have their own mini travel-without-being-stopped-for-identity-documents area, the Common Travel Area.

Without googling, I assume it's because somewhere like the Netherlands or Austria needs to placate the far right with symbolic nonsense, that causes Romanians unnecessary delays, and makes them feel like second tier Europeans.

That is my own impression.

That is not at least Austria's official justification.

There have been other people who have made other claims with varying degrees of justification. I have seen Romanians who feel that the veto has been aimed at disadvantaging their ports, as lack of Schengen Area membership is an unpredictable and sometimes-quite-long delay for trucks moving freight. I have also seen some Romanians talking about some demands for lumber concessions by Austria that Romania did not grant; these people felt that it was something of a shakedown. The fact that Croatia (with some similar issues) was given membership frequently is pointed out -- unlike Romania, Croatia is a popular holiday destination for Austrians, and Croatia not being in Schengen would be an inconvenience for Austrians, though arguably similar migrant issues would also apply to Croatia. Another point that is often raised is that some assertions by Austria as to Romania's membership causing migrant problems are based on a poorly-supported-and-likely-not-accurate claim by Austria about illegal migrant movements derived from monitoring mobile phones.

But whatever the case, it is something that I have seen a number of Romanians be quite upset about.

I will say that even if one takes Austria's official position at face value, it's that EU migration policy needs changes and that they're basically using the veto on Schengen as leverage to obtain those changes. That is, they aren't saying that Romania or Bulgaria have actually failed to hold up their end of the requirements. So I expect that even if a Romanian did agree that the official justification was the real reason, said Romanian probably wouldn't feel very sympathetic to the veto.