I think there are several factors involved here.

One is attrition. A lot of older DVD only players are dying and need to e replaced.

Nowadays, almost any Blu-Ray player (except the very cheapest) offer a plethora of Internet apps thrown in. Go up a few pennies more and now wireless is part of the mix. Blu-Rays are simply cost effective and are now more than simply disc players.

The discs themselves are getting cheaper. I was in Walmart this week and they had bins upon bins of Blu-Rays on sale for around $8 or so, and not just titles nobody wants. Granted,not the most current releases but still some pretty desirable titles. Many I already own on DVD. If I didn't, I would have been mighty tempted.