Overblown or a Real issue: Disc Rot.

So I was talking to a friend / fellow movie collector and I told him I had order a dvd off of ebay, mostly because it's not available on Blu Ray and I'm giving up hope it will ever be available on Blu Ray. He started being very critical of the fact that I bought a DVD, not for any obvious reasons. He was saying DVDs are notorious for having MAJOR PROBLEMS with disc rot and in a few short years the DVD format will be dead because 90% of dvds will be unplayable. He goes on to say Blu Ray and 4k doesn't have these issues. I know he doesn't own a single DVD only BR & 4k. Now I don't deny Disc Rot is a potential issue. I own several dvds from the late 90s, like around 96/97 when the DVD format was first being introduced and they all play fine with no issues. Although my collection is a very small sample size. What are your opinions on this? I think he's blowing this potential issue way out of proportion. Do dvds suffer from disc rot whereas BR & 4k do not, or is this completely untrue? I think 4k is too new of a format to say one way or another at this point.