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Yeah, I'm DEFINITELY never playing 5E. Getting rid of bonuses and replacing them with a method that adds more randomisation1. Under the guise, one presumes, of "simplification." *sigh* You see this sort of thing in bad wargames rules all the time. The emphasis on "make the rules be simple" over "actually consider what the rules are going to do." Gamist over simulationist, too.
1Yes, more randomisation. Two dice doesn't make it more likely as you're still WELL instead statistics of small numbers issues. Yes, it theorhetically statistically gives you twice as much chance to obtain a result. But as the degree of randomisation increases, the actual spread of obtained results drastically increases. The reason Accelerate & Attack has an average dice table (for 10 to 100) is that I ran an analysis and we discovered that taking the average of the tens and rolling the remainder actually gives you more randomisation than rolling all the dice. But in order to get to that point, you need a large sample size. Two dice is not it.
As a further example, in AccAtt, you can get Torpedoes in Class from 1 to 10. A Class 2 Torpedo does the same damage as two Class 1s, and has the same accuracy. But, in practise, the accuracy is of multiple class 1s in modally much more accurate, since you will roll a lot more dice per round. (Salvos of 3-4 per vessel and 2-3 vessels per squadron is not uncommon.) The same issue applies to Bolts (though they have some other advantages at higher classes). Whereas most other weapons roll one dice per class, Bolts roll one per weapon. Which means that a fleet armed with Bolt 6s is a lot less scary than one armed with Beam 6s, since the former is a very swingy weapon. Sure, it'll hit hard when it does hit... But the chances of you having a bad day and rolling low is much, much higher, since you're rolling six times less dice.
Now, if 5E's system was to give you additional extra D20s instead of modifiers, I could see the point, maybe. (By the time you get to rolling four of five D20, you're actually be making something of a difference.)
But it's a silly trade-off to avoid using basic maths otherwise for "playability."