They can be super good, they're just not solo queue friendly, there's a lot of jobs that fall in that bracket. AST is not exactly solo queue friendly either, the safety net is just a lot larger than the one given to SCH; which puts it in a reasonable spot overall. And yeah what I'm saying is blasting for the sake of gauge is bad usage of it. It's a peel and a pseudo interrupt as a priority. Also not only are you counting the hot in solace, but also making the assumption that you are holding 3 lilies. Given how you generally want to maintain your hots for miserys to support burst; this is unlikely unless the other team is really bad at pressuring, and even then you'd probably just burn on raptures for more miseries. Seraphim is overall underwhelming, unfortunately this isn't a problem exclusive to PvP, it's not that great in high-end raiding either. Maybe Melo can expand on Lily management at high level if he sees this, because I've got around 450 games on 3 healers (2x WHM 1x AST) and whilst they're all in plat, doesn't mean I'm doing it right lol.

Also Bloodbath is very rare, there are a very small selection of good players that will take it, I think the only one in Diamond on Light that does is Cyne and he pairs it with Chiten; but generally it's not that good. Drain is also rare for a number of reasons. The primary one being there are a very low amount of casters on EU, and the ones that we do have not all of them take drain; myself included; I prefer Ward because I would rather have the HP pad over an ability that requires me to be at a lower amount of HP to outpotency Manaward defensive (but obviously, it's the better offense/defense additional).

Overall though, Biolysis and OGCD/resourceless healing are probably some of Scholar's main strengths; but as mentioned - it's not solo queue friendly and as a result yeah, I'd accept the vast majority of the time you would gimp your team by playing it.
The reason why Chaos players are memeing on it are the same reason people in other DCs too, the vast majority of people who think they can play it actually can't and the ones that can will struggle if their team isn't very good or needs a slight healer hardcarry to succeed because they are not that good defensively. I'd love to see a couple of play it next tournament (Clash of Light) but think it's unlikely lol. It's a shame the best SCH players don't post here because I'd obviously love insight from those who have laddered on it at a reasonable elo.