No you aren't. Daily story mission gives ascended mats and can be done on each of your characters. Same for daily public event mail. Same for daily public event completions.
The amount of materials needed to reach level 28 isn't particularly large. Unless you're pushing all your gear to 29 (why?), you don't need a ton of shards.
On top of that, I'm not sure people have realized that higher attack does precisely fuckall for you against enemies of a lower level, it helps if you're fighting higher level enemies.
Or to put it another way, if you're blowing all your energy and shards upgrading all your weapons and armor, you're wasting them for no good reason.
Armor in particular should only be capped if it is either a) raid armor that goes to 30 light or b) you're pushing to hit 29 so you can do the hard mode raid.
Otherwise you can reach 28 reasonably easily (especially easily now that queen is giving you free chest/helm, that means you need a whopping 65 marks or 130 marks to cap out in armor depending on what xur has for you).
Once you're 28 you can do the weekly nightfall easily, and all other existing content outside the hard mode raid without trouble.
If you want to do the hard mode raid right now, then yeah, you're going to have to triple farm dailies and weeklies with three capped characters, but for literally any other content in the game, you do not need to do so (and frankly, doing daily and weekly events on three different classes sounds a hell of a lot more fun to me than farming engrams, ymmv).
The sheer amount of misinformation and FUD being talked in this thread is unreal, I think I'm going to take a hiatus for a few days until things calm down or we get a dedicated gameplay talk thread in community or something.
There's very little point in attempting to ask or answer gameplay questions in the OT when the majority of posts are throwaway rants that we've seen posted literally hundreds of times.
On top of that there's a ton of misunderstanding, confusion, or outright false complaints about the way loot and progression function in the game. A lot of that is on Bungie, they fucked up by not laying out progression clearly, but the information is out there, if you care to look for it.
Hell, a lot of the information is right here in linked posts in these threads, but again, it's drowned out by the noise.