It's worth noting that there's pretty important caveats to this. In single target healers were indeed a good way behind. But in AoE, healer DPS was seriously underestimated back then, laughably so at times.
At the very start of HW I could out AoE any DPS except a SMN in neverreap on Scholar pulling 1000dps+ on trash. In Stormblood I never figured a means to reach the same silly numbers but for the most part I'd be right there with a well played DPS' numbers on trash still routinely beating decent players if they weren't on a particularly strong AoE job.
Also keep in mind that it's very possible for them to add extra depth to our DPS without inflating the numbers by simply tuning the potency back down or even using the stat crunch as a means to camouflage how our damage scales with MND relative to DPS jobs and their mainstat.