It may have had much more to do with the fact that Win 3.11 had shitty text display than with any real problem with Arial. But Arial really did look horrendous to my eyes compared to Verdana, on the same machine. I do think that had I had access to Helvetica back then I would have liked it more. But without a time machine it's impossible to tell.
I also grew up with computers and started looking at text on screens from the fourth grade. I'd had a long time to develop my eye for type by the time I was writing papers in high school. I could look at a page of printed text and tell which (Microsoft) font it was using, I doubt many kids back then could. I do think I'd have been able to tell Arial from Helvetica. There are quite a few differences between the two. Enough that my practiced eye would be able to tell the difference. Not that my programming day job affords me much practice in that regard.
Arial just looks clunky compared to it. Helvetica's loops are more rounded, they stand out more boldly from the staffs than Arial's. It's a much more confident typeface. Arial's 'e' looks squashed, it reminds me of a trollface. Its 's' has the same problem, though not as pronounced. Helvetica's versions are much more elegant. Helvetica's numerals are far nicer than Arial's, in particular the '1' and the '2'. The tails of the '6' and '9' daringly overhang the loop slightly in Helvetica, no such eccentricities in Arial, except for the 'f', whose top pokes out past the cross. It would ordinarily be a fine quirk, but in Arial it just looks out-of-place.