That DVD players appeared on the market well before DVD recordable media?

Also, do you remember the format war of DVD-R and DVD+R?

And finally did you notice that some players list neither, one or the other or both?

In closing I note the + or - on the media and include a note that the player's media compatibility list must be checked. I've had no issues that you speak of and since I put them in boxes or sleeves the scratches issues have been neglible. Then again I pick them up from the edges as noted in the care and handling guides.

As to extreme light, this issue applies to vinyl LP, VHS tape and more so nothing new here.