That's the problem with constantly going back to FFlogs. There is no direct 1:1 comparison when you're looking at fflogs the way it is right now because when you look at the top MCH and BRD, it swings widly because of clear times being a difference of over a minute, and/or astros being present (and balance being given to the MCH, no less). I'm not arguing that on record BRD is doing the same amount of dps as MCH, but that doesn't prove that BRD is behind MCH in dps objectively. This was exactly the same during gordias, except it had gone on enough times that you'd sitll have some resembelence of similiar environments between the two (and BRD was still ahead by a few digits, on top of better group dps), and MCH representation was only at double digits at the time.
The uptime on foe combined with RoD has always put BRD ahead of MCH even with 1 casters during 3.0, as far as raid dps was concerned. The functionality of hypercharge also makes it less flexible to use for damage debuff or doubled regen without directly affecting MCH's personal dps (since it is a turret potency boost). The change to hypercharge has leveled the field, if not shifted the advantage to MCH a little bit.
It's a problem in the current meta just as how much the previous meta was favoring BRD with foe reqiuem with a caster and healer dps (which is still applicable provided the group is capable enough) If you say it's a problem with the meta, then sure. But we're just gonna be moving the problem around if we give BRD an edge toward caster comps (which means you won't have melee, or just stick with DRG, because the crit buff is just too good to pass up compared to other buffs).
And even then, this only really matters when we're talking min/maxing, something that you really shouldn't make a big deal out of unless you're going for world firsts.
And then throw out casters? Giving BRD a piercing debuff doesn't even make sense because it's not going to level them to where MCH is. Again, Yoshi's stance on BRD/MCH is that they both sahre the same role of "support" dps. MCH is not a full dps job as much something as the melee/casters are.
Then stop bringing up damage or the "dps gap" as a thing then, because that's what most of your points come back to. If a fight isn't designed around BRD, that's very much so the case for the 3.0-1 days for other jobs when they weren't preferable. You also mentioned that they could make MCH a pure-dps job instead of dps-support, making BRD once again uncontested in party compositions.