Honestly guys he's completely right.
Something like Corruption with a vendor so no rng is an extremely good thing as it allows you to not only further progress your character after reaching the best items but also allows you to customize your character to a tremendous degree.
Maybe the rng/proc based stuff isn't so good, but the flat stat increases (Expedient etc..) are awesome and definitely need to be continued in Shadowlands. Alternatively we should at least be able to upgrade the item level of our gear like back in Cataclysm/Mists. If we can't in any way upgrade our gear it's going to get really boring really quickly. Plenty of people want to keep progressing on their main character after reaching their best in slot gear.
The answer should not be just play an alt, people are attached to their mains.