Whilst no you're not saying make them generic, but you are asking them to remove one core aspect of the job. If you meant just on an aesthetic level, you could have just said that. But your previous comment was about removing them because they don't work and that they've allegedly tried to make them work (when they haven't) so they might as well get rid of them.
Even then as I don't want you to have a concussion, I understand where there are attachments to the egis and can give some reasons:
- Mechanically they work differently to Demis. Demis come in, do their thing for a bit and go. Egis are around for the full fight, they DPS separate from you, slightly spread enmity. Ifrit could stun, Garuda could extend the duration of your DoTs, both Titan and Ifrit could shield. Titan was a psuedo-tank for soloing. Even useful in tankless deep dungeons. This is of course pre-ShB egis. Ifrit also could also add another DoT through its Enkindle and Garuda could give bit more of a burst with hers.
- Lore. This is something that matters to some players, especially the RP community, which is very strong in FFXIV. They've built whole lore and context behind egis overall, there's a lot behind them. By removing egis all together you end up invalidating it. There's another thread complaining how old quests no longer make sense with certain abilities removed. Imagine doing the level 58 and 60 job quests but Dreadwyrm trance and Death Flare are no longer a thing, it messes with continuity. Fair enough none of that may matter to you, but there are people who're quite deep into this sort of thing.
- Some find Demis to be obstructive or too big (I don't, but it is a complaint I've heard, but at least for them it's a temporary thing), whereas Egis were designed with that thought in mind. And the reasoning they gave back in the day for how they designed them.
- Some people just like having a pet that can follow them around and they can dish orders to. Many MMO's have such classes where you can do that. Demis are temporary, do their thing and leave.