IIRC it did...for the weapon, but it didn't calculate all the additional bonuses from gear etc. so it wasn't even really useful. You'd have lower DPS weapons outperforming because they had greater benefits, or you'd have weapons with higher/lower RPM's benefit more/less from your bonuses which cause the DPS calculation to be misleading.
If you want to do the calculations, sure. But you'd have to do them in D1 too to account for all the other bonuses. Honestly I like having the raw damage/RPM and reload speed front and center, because it makes it easier for me to napkin/mental math some shit. Like my main AR build uses an AK-M because I get more overall benefits from it compared to just about any other AR from what I can tell. Lower RPM means more uptime for Strained at 50% bonus crit damage, most of the downsides you can't calculate like accuracy/stability and stuff you can calculate like its slower reload speed are all offset by Braced (vs. Obliterate which would be more raw damage), and with a higher base bullet damage I get more benefits out of my crit damage than I do out of faster shooting weapons.
Oh don't get me wrong...overall the stat system in this game is a god-damned nightmare, terribly presented, remains opaque and unexplained without going online to find the theorycrafting and damage calculations folks have worked out (damage to armor is calculated after everything else? increased vs. amplified means what? etc. etc.) and missing gobs of information left and right. But IMO I feel no less informed in D2 than I did in D1, probably more informed actually.
A lot of games have this problem, sadly. Looking at PoE, which is supposed to be one of the more transparent (though still confusing) games on this just take the term "Nearby". It's on dozens of skills/items/talents, and depending on which one it is it has vastly different ranges that aren't explained at all.
We all just need to accept Ion's tooltips and call it a day. "Does some more damage, but not a lot more, just a bit. And sometimes procs a buff which makes it do some more damage, a lot more."