It changed quite a bit actually, at least in terms of what made legion gameplay good. No it didn’t receive groundbreaking changes but a lot of what was fun in legion was almost all gutted or changed.
In the previous expansions before legion especially MoP/WoD we had many tools for dealing with “downtime” or filling. The playstyle in BfA isn’t even remotely close to what WoD or MoP had. Then you take a look at legion and you’ll see a lot of the main things that made Hpal fun were removed and yes it’s the same for most classes which is why class design is a hot topic currently and mainly negative.
I won’t talk about aura of sac itself since it was blatantly OP but we can run through the basics:
-Ilterendi giving you a small rotation inside of the buff window to manage.
-Maraads (in ToS) adding Lotm into the playstyle which also added a pseudo-rotation and also introduced some min/maxing you could do with AoS that made it even more insane. Was also great for beacon healing.
-Power Of the Silver Hand. Nothing crazy but in dungeons when this procced you essentially had an extra LoH. This was really nice in higher keys in m+ where you’d watch for this often.
-Holy Shock crit. Changed from always doubling your crit to a flat 25% (and now 30%) base crit chance. I admit I’m not sure this was a good thing for the spec but it definitely sped it up and was undeniably fun imo.
-Tyr’s deliverance. Was really nice for 5 mans. Essentially a small aoe heal that also buffed your healing on all targets hit. In raids it wasn’t bad either and after the buffs it received through traits it felt nice to use.
-Nighthold set bonus gave us 2 charges to IoL. This was really fun imo as it allowed you to pool 1 extra charge for a good moment if it was going to get use before HS was off cd.
-Divine purpose. This was a talent that sat in a row with HA and Prism. Prism wasn’t viable at all in legion and still isn’t in BfA however DP spiced things up by adding an extra proc into our playstyle. This is no longer an optimal due to being on the beacon row which relegates it to a “niche” talent in most cases.
-Highlords ring. This legendary allowed you to take 2 talents on the same row. Many took DP/HA which added an extra proc to the rotation -and- an extra CD.
These are just some things that were removed and ultimately for me made the spec feel like a gutted version of legions design which is basically what it really is. I’m not sure too many people would enjoy the fact the spec they liked last expansion was gutted and then hardly changed afterward so it’s a shell of what it was.
I’m not saying we need buffs. I think our performance is good. I think our gameplay is just really stale especially after losing artifacts/tier/legendaries. Not saying the sky is falling either, just that it’s clear that the spec didn’t get enough treatment throughout beta and was left with a lot of removed interactivity and flavor while not much else was added outside of AC.