Endwalker White Mage has Issues

[Silver-Strider]

In that situation, IMO WHM actually has the best chances of dealing with such a pull. Why? Holy. I don't know if the WHM used it, but it is what makes WHM the best (easiest) dungeon healer by far.

For the other healers, I think SCH and AST could probably survive that situation as well, but with more effort needed (and I'm not sure if SCH would make it mana-wise). SGE would have (IMO) no chance in hell with the limited spells they have at that level (Kardia, Soteria, (E) Diagnosis, Physis, Druochole).

WHM has issues, definitely. But there's no need to downplay it's strengths either.

Holy is a band-aid and doesn't solve the issue, it only helps to cover up the flaw that low level WHM has nothing to help it heal with when crap hits the fan. Yes, it's a great skill but the fact was that I doubt the tank would've survived if the WHM stopped to use Holy at all. I did see they had to burn Swiftcast on Cure 2 just to keep the Tank alive mid transit on the pull after the 2nd boss and there wasn't really time to cast holy with the volume of enemies. The 1st pull they might have been able to use a Swiftcast holy but I don't expect a new player to really pull off something like that. One of the most common pieces of advice new players receive for Healers is to not DPS until you feel comfortable doing so, so I can't fault them for not using Holy.

As for the other healers, SCH has Aetherflow at that level so they'd have less MP issues then WHM.
SGE can heal on the go so it kind of comes down to how much the SGE can switch between rotating DPS and heals

[Sarim]

Holy is a band-aid and doesn't solve the issue, it only helps to cover up the flaw that low level WHM has nothing to help it heal with when crap hits the fan. Yes, it's a great skill but the fact was that I doubt the tank would've survived if the WHM stopped to use Holy at all. I did see they had to burn Swiftcast on Cure 2 just to keep the Tank alive mid transit on the pull after the 2nd boss and there wasn't really time to cast holy with the volume of enemies. The 1st pull they might have been able to use a Swiftcast holy but I don't expect a new player to really pull off something like that. One of the most common pieces of advice new players receive for Healers is to not DPS until you feel comfortable doing so, so I can't fault them for not using Holy.

As for the other healers, SCH has Aetherflow at that level so they'd have less MP issues then WHM.
SGE can heal on the go so it kind of comes down to how much the SGE can switch between rotating DPS and heals

You are right in that Holy is a bandaid really. And I think it's the big thing that keeps the devs from making any significant changes to WHM. But still, as long as its there, it will give WHM the edge over the other healers in a situation as you described.