While I completely agree there are people buying/selling carries for shinies that drop from ops or specific titles/achievements (and it costs a couple more 0s than you mentioned), I don't think full nim carries specifically for gear will become a thing outside of that already small community. As expac progresses, max gear rating to be obtained from other types of content will increase and players will be able to get it outside ops, so unless you want to get max tier on week 1, there's no need to worry.
People flexing their 'raid tier mount' on the fleet and 'looking down on the common folk' as you said it is a very elitist mentality, and if it's done by people that got carried to the clear... it just says a lot about them. Not to say that nobody should be proud of their crests/wings/etc, those items are difficult to obtain and require a lot of time progging and I'm always happy to see people that put a lot of their time and effort succeed. But I'm going off topic here.
You probably wouldn't believe it but I've seen tons of players in 280s random gear do better than those in fully augged 306 set gear, so I don't judge them by what gear they use but whether they let the group know they're new to a certain mm flashpoint or sm/hm ops and whether they listen to explanations/follow mechanics. You can still max out your gear and have a reputation for being a bad player.
Example from the other day - my guild was doing a lblo (last boss lockout) run of a certain hm ops and we had to pug a dps. We got a person with 306 gear with gold augs. When we asked if he needs quick explanations on the mechanics he said he's cleared it and got the achievements, so we were good to go. Then he continued wiping on the first phase because he was standing where he shouldn't and died to the aoe. The pug we replaced him with was in sub 300 gear but was willing to listen and learn and although we didn't one shot the boss we cleared it and gained a new guildie.