Parmandur
Book-Friend, he/him
Conversion guides would be a really cheap way of suddenly providing hundreds of adventures for your game, instantly turning it into an incredibly well-supported game.
That said, it then removes the benefit of an OGL-style license, as third party support fills that same role.
I'd say it multiplies the advantage, rather than removing.
A decent conversion guide for the past editions would make 5E the most supported game on the market, and having a decent license would mean that would only grow.
Heck, a 3.5 conversion guide (not that difficult) means anything Paizo makes is as good as supporting 5E, let alone 3rd party PF support.