The assumption that Ukraine's conventional long-range strike campaign would not make a difference was always an extremely odd one. People arguing against it portrayed a fundamental lack of understanding of strategic airpower provided by modern conventional missiles.
I've always understood that argument to be typically pitched against the strawman that "make a difference" meant "win the war" which is true but vacuously so.
Additionally, the previous campaign was reminiscent of the Houthi campaign against the Saudis which ultimately had little impact. As the posts note, effects only started to build once Ukraine was able to achieve the requisite tempo of attacks.
Only one profiting from that assumption has been Russia. And so happens that the most effective strikes are those done behind the frontlines deep in to Russia. Refineries and weapons industry facilities being burned to the ground is not a small blow to Russia. Flamingos will be flying unlubed.
If everything claimed by pro-Ukraine commentators is true, Russia is well and truly screwed. Russian manufacturing relies entirely on scale through maximum consolidation, in factories 1~2KM away from the "western front". Lot's high value strategic targets within the deep rear. If it's all true.