Lol, no worries.
Well, you'll be glad to know SMN is a lot less mobile is 70 and 80 content. In 70 content, Ruin III is stronger than your Garuda Rite quickcasts. You get more mobility at 86 from getting Astral Flow abilities from your elemental summons.
I didn't get to really experiment and do optimize runs in the last eden tier on caster. I can only check the top 50 on fflogs. I know RDM was slightly weaker than SMN back then but if you look at SMN vs RDm on E9S and E12S II, it was 26% vs 20% in favor for SMN for E9S and 43% vs 38% in favor of SMN.
Right now if you check P1S, 61% for RDM vs 19% on SMN and 57% vs 28% in favor of RDM.
Funny enough when you look at pure damage on fflogs. Both in e9s and e12s RDM make the top 5 having an overall beterr damage output than SMN despite SMN having more exposure. Right now in Pandaemonium, funny enough, SMN is beating RDM by like 20 DPS on p1s but is losing by like 150 dps on p4s.
My guess is with the craziest setups, you can probably have the underdog pull an upset. However, the exposure of both jobs is currently what is worrying.
I think in general, downtime is bad for everyone but in current example. I doubt any minor melee combos would have a bigger impact than having to unsync Bahamut on buff windows. It's straight 1800 potency you're losing in that burst. The downtime is also only 9 second. The issue is it happens during a buff window so buffs are delayed. You can delay Searing Light but SMN's current rotation doesnt allow you to just delay Bahamut, you'd be spamming Ruin III for 11 seconds, arguably the worst choice you could make. The current top SMN on p2s can,t breach 8k rDPS while RDM is at 8141 (roughly 150 more)
If anything, in ultimates, you are required to move more, you have more mechanics to deal and they are faster and more deadly. But because ultimates are also extremely rough, raise and magick barrier are likely just superior choices I'd feel since you aint really looking at speed running ultimates.
I'm pretty sure his goal isn't to put a competition between the jobs but he just want to clarify. Because it's true SMN always had the bigger end of the stick in term of firepower but RDM brought other stuff.
People that just bring out the RDM vs SMN are usually just saying dumb stuff like, "mobility should be taxed and braindead jobs are expected to deal braindead dps"