I'm sure they were more plot-relevant, too? Whereas Awakening/Fate always seemed more "LOOK AT MY CHARACTER QUIRK! I HAVE A QUIRK! LOOK AT IT!!!"
I will criticize the armor (or well, "armor") designs all day, but, I must disagree on the latter point.
For instance, I refuse to believe anyone actually thinks Lucius is a deeper or more interesting character than the same-archetype Libra or Forrest in spite of the two of them being admittedly even less relevant to the overarching plot than Lucius who is shamefully, imo, very underutilized. And then of course older games had so few supports that he got no further characterization outside of what we basically already knew from interactions in maps. A bit of a friendship with Serra I guess? That's it really.
I think people just don't read the support conversations in Awakening and Fates or something. They really flesh out a lot of characters, above and beyond previous games.
I also prefer characterization being delivered via supports as it means a character will never necessarily fade to irrelevance.
I do think more focus could be shifted to friendships or rivalries from romance in the next game, but I'd be horribly disappointed if they went back to a style of most characterization being in the plot, thus inevitably leaving certain characters in the dust and left to rot.
Like, seriously, outside of designs I'd take the casts of newer FE games over most FE10 and before characters any day.
That said, with Echoes, such supports are cut down on. Yet through other interactions in towns and such, they make the cast of Fire Emblem Gaiden actually feel like real, compelling characters.
I dunno. I just get really peeved when people act like the Awakening and Fates cast are nothing but tropes. Some are yeah, especially via the localization's changes (mostly a very good localization but damn did some characters get hit for the worse, poor Ryoma). But not anywhere close to all.