Being a level 30 myself and usually joining raids full of level 30s, I've never heard any of them say only those with full raid gear earned their level 30. Also, to equip full raid means you have had to at least beaten the raid on hard mode to which I say that in itself is an achievement and even if they were lucky enough to get the helmet on their 1st, 2nd or 20th time, they earned it (unless they cheesed Atheon, then gtfo). I got lucky with my hunter, I was level 30 after my very first raid getting all but helmet and using exotic helmet. Then I did the hard mode after and got Mythoclast on week 2, being one of the few people in game with it. Was I lucky as -blam!- with RNGesus? Hell yes I was, I was so blessed. However, I managed to complete not only normal mode at week 1, but hard mode as well, so did I and the rest of my team deserve our gear? You bet your sweet ass we did. However, those going for the light level 30 from Iron Banner, holy... I got my Titan to rank 4 just to get boots and gloves and I can promise you that anyone who does the Iron Banner for their light level 30 gear, kudos to you, you really do deserve that gear as it is no easy task to complete nearly 100 wins.

I'll be honest with you I've never personally encountered anyone like that that has said you're only an "earner" with straight raid gear but whoever did that is a fool. Personally however you get 30 is up to you because technically speaking you have to raid at least once to get 30 regardless. Also, Destiny is diverse, if crucible is your thing you should have every opportunity to get 30 as someone who is big on raiding and PvE. I think this should also expand into how you acquire faction items beings not everyone plays crucible frequently such as myself, though you can get faction reputation via PvE they should make a universal system in which factions can take vanguard marks as well. But reverting back to the main topic, to get 30 you have to either go hard in raids or you have to go hard in Iron Banner either one should merit the respect of other guardians if you can achieve light level 30 which for crucible players in my personal opinion is much more noteworthy beings it'll be the struggle for shards as well.

I don't believe you can actually "earn" raid gear

*shrugs* can a destiny player actually earn anything when just about all rewards are RNG? just about the only way to actually work towards something is if you walk around in circles collecting materials, exchanging them for marks, then Purchasing Legendary Weapons and Armor. Some people have done the raid 10's of time without getting a full set of armor some get a full set on their first try some people find 7 legendary engrams in a day some have yet to see 1 in 500 hours of playing. some people get Exotics and Legendaries from the Nightfall I know someone that has only ever gotten Coins for the same work ...which is kinda funny when some people make a stink about others buying from Xur, weapons that they think they have "earned" Its all RNG, Hope everyone gets lucky and hits Rank 30 how ever they want. Pray to RNGesus and hopefully people throw about any notion of Earning anything in Destiny

I think it's because they likely spent a lot of their time doing the raid several times a week to get their gear, and they feel cheated since now all you have to do is spend a few hours getting to reputation level 4

Why do you care? people who say there is only one legit way to get to 30 are worth less than you, just play the game and have fun, don't ponder over what other people think.