It doesn't hold any interest for me, quite frankly.
If they do go with this idea, I think it'll be McMahon vs. Trump for WM 30. Trump made a "challenge" to take on Vince at WM 30 so if they have a match for Vince, it'll probably be that.
For me though, I've seen Vince in too many feuds & matches in the past and it just doesn't feel special anymore. On top of that, Vince will be 68.5 years old come WM 30 and Trump will be 67.5. So that's a wrestling match between two non wrestlers, including one who hasn't done anything athletic since the early days of his comb over, that are a combined 136 years old. It just doesn't do anything for me.
On top of all that, Vince simply isn't the guy he once was physically. At 67 years of age, how could he be expected to be? He recently had hip replacement surgery and is fortunate he didn't get hurt with he took an F5 from Brock Lesnar. It probably didn't do him any real favors. During his fight against CM Punk, according to reports, Vince was feeling the effects of the match for a couple of weeks. There just has to be a point in which Vince looks at things and says that it's ridiculous for him to get in the ring.
That's not to say that the idea wouldn't appeal to a lot of people. Live crowds especially love a "feel good" moment and Vince going over Trump, as a babyface, could be just that. Donald Trump "wrestling" in a match is something that would generate a ton of mainstream media coverage, even more so than usual for WrestleMania. WWE made the wrestlers and the wrestles alone the focus of WM this year. Every year, it seems there's MASSIVE hype around the various celebrity appearances & involvement at the event, sometimes at the expense of the wrestling matches themselves. This year, it was all about the wrestlers and I personally think that's how it should be every year. Even though some panned the event because of it's lack of unpredictability, which was to a fault in some ways, but it was all about the wrestling & the wrestlers this year.