They would have huge problems as far as transportation in and out of there, as well as with corporate hospitality.
Possibly a bigger problem would be where to put the spectators. The bottom line is that The Royal just isn't gig enough for an Open Championship. It is a wonderful and underrated golf course, no question, but it just can't do it for a big tournament.
I met with Carwyn Jones a few years back about building a premier golf facility on the property around Kenfig Pool, Sker House and reaching up the the brownfield area south of the steelworks. A major facility with a few courses, one of which would be an Open caliber course. I had Eric Iverson stop by and take a look at it and he was knocked out by the area. The dunes land there is truly awesome.
There wasn't the political will for building it unfortunately and I doubt they would ever would be. No great project is done without some kind of anguish and battle and there is no appetite there for it. The will of a few will always override the best interests of Wales.