If Blizzard truely supported soloing old dungeons as a feature, they would have balanced the classes accordingly instead of only a few select classes/specs able to solo almost all content and other classes having almost no chance unless they outlevel it severely. Most transmog runs to 80/85 content are still done in groups.
Removing the group requirement and putting pets into the super old raids would just be a temporary measure, because a thing like item squish is a massive undertaking. This kind of token effort really doesn't sound like support to me.
Also, I read the Chinese interview. Unless the interviewer mistranslated GC's words, the certainty was very strong: "...we WILL do the item squish.." (...我们会压缩...)