Yeah, ARR to HW was an awful time to solo queue as a DPS full stop really.

For whatever reason late Stormblood as a DPS didn't feel quite so bad to me at least (I was playing Redmage a good bit for roulettes and alliance) but that's 100% subjective and I can't back that one up with anything so I could be wrong there. I suspect early SB was awful with both Sam and RDM being popular+decent at the time.

I don't really think the ShB healer gutting was in response to SB directly thought, I'm pretty confident it was a second go at what was initially started with 4.0 SCH. Just this time they didn't quite such a problematic hole in the kits (Remember 4.0 left SCH with no spammable or mobile AoE) so were able to stick to their guns on it. The plan was already in motion.