Not to single you out -- because many typographers share your opinion, it seems -- but how can a ripoff of a good font not be a good font on its own? Okay, Microsoft ripped off Helvetica, and Arial is lame because of that. I get it. But Arial being an ugly, useless font because MS made tiny tweaks to some of the letters, most noticably on only one -- the capital "R?" Where's the logic?
neema_t said Helvetica and Arial are like a Ferrari 355 and an MR2 with a bodykit (presumably made to look like the 355), respectively. As a car enthusiast with little to zero interest in the study of typography, I'm going to have to borrow that analogy.
In my opinion, if Helvetica were a 355, Arial would be a handbuilt 355 replica that is almost completely indistinguishable from the real thing, its only flaws being slight variations in body curvature and somewhat goofy "Rs" on the Ferrari logos. There are certainly instances where a real Ferrari, or Helvetica, are preferable over a fake kitcar or ubiquitous font knockoff -- a track day, professional design work -- and if it's available, there are few reasons to not use the genuine article. However, in an everyday instance where the choice of car/font is beyond your control -- borrowing a friend's Ferrari knockoff to commute to work because your car is in the shop, or posting on a forum that uses Arial, or taking a class that requires Arial for papers -- what's the big deal?