Wlad would jab the head off him for four to six rounds before being decapitated by a Wilder special out of nowhere
The jab should keep Wilder honest and we know he can't fight on the back foot. But Wilder's ugly ungainly way of getting his offence going would cause Wlad some problems. Wlad was very cautious until he got you figured out and the longer your in with Wilder the more chance he lands the nuke. Sensible bet is a Wlad KO, Better technique, better feet a good clincher and massive power of his own...but he's very up right Wilder would have the proverbial punchers chance.
Wilder went life and death with Spilzka and was losing to C level heavies like Washington. 2017 Wlad would have derailed the hype train before it had left the Lions Den station.
Because boxing matches like this don't happen, he has a professional problem. More precisely, it is less and less a sport, and more and more a business. Accompanying phenomena are: possible 5 champions in each category, 17-20 categories, decreasing popularity of boxing, increasing popularity of mma ... Not to swear ...
There's a reason why Wilder never tried to unify, we all know the stories of what happened when they sparred. Wlad was simply a far better boxer and would land a big punch well before Wilder could and with Wlad's power if he lands clean, it's lights out.
Wilder was in a few Klitschko camps around this time and the years before. It's pretty well known how that went down... I think you'd need a 43 year old Vlad before I'd favor Wilder.
Wilders team bottled it against Wlad and wanted nothing to do with him. If it actually happened considering how and Wilmited and wide open defensively Wilder is , Wlad would KO in a couple of rounds. He'll wlad could come of retirement now and probably still beat him.