To me it's clear the order of events was:
Hey R.A., we need a new sidekick character to put in your novel. flips through Unearthed Arcana Hey how about this? We can use it now that Gary is gone, right? Crystal Shard and especially Drizzt becomes a stunning success but drow player characters have already been thrown in the naughty pile for 2nd edition. Aha! Let's rewrite rangers to keep the fan-boys happy!
Okay, so here's the slight problem with this theory:
1.
The Crystal Shard (Icewind Trilogy) was released in 1988- same time as the 2e was in playtesting.
2. The next two books came out as 2e was being released (book 2) and afterwards (3). Drizzt was getting popular, but still wasn't an iconic character ... yet. That wasn't until 1990 and the beginning of the Dark Elf Trilogy. Also? Please kill me. I have now typed that name so many times I might know how to spell it without looking it up.
3. So the timing really doesn't work. You'd have to have the 2e team specifically told, "Hey, we have this character in a set of books coming out, and he's going to be incredibly popular, so we need you to re-write the rules for him."
4. That would be a pretty big deal- and kind of weird given that neither the creator of the character nor the writer of 2e knew about it!
5. Further, it would be a pretty weird instruction. "So, the character is a dark elf, right? But here's the thing- the character is going to be so popular, and is going to make it really, really, really popular for people to play dark elves. So what we want you to do .... No, what we NEED you to do ... is to get rid of dark elves as a playable option and let rangers dual-wield. MMmmmkay? And then make sure no one ever learns the secret!"
I mean, anything is possible! But given that all available evidence points against it, and given that they got rid of dark elves as a playable race ... and that the people involved say it didn't happen, and that the timing isn't quite right given publication schedules ... seems a bit of a stretch, doesn't it?