I do remember a ton of posts and threads about raiding participation being down because it was easier and/or more efficient to gear in M+.
Many people would clear heroic and out gear it before getting AOTC and in some cases before they even set foot into a raid. This happened even in 8.3 when they removed titian forging.
If it is something that is impacting the devs decisions then I think my suggestions particularly of having different tier sets would be more beneficial then what we are currently seeing.