It might have made a difference. I don't know. However, it's not Mitch's fault. Both of our candidates finished strong with over 2.2 million votes and it would have been enough if we weren't dealing with these massive mail in ballots, which makes it easier to commit fraud. Kemp allowed all of this **** to happen and broke Georgia election laws to do it.
If Republicans didn't make it easier to vote they would have won! That sums up the current R party succinctly.
It was a long parade of stupid mistakes and unforced errors, and nobody forced any of it on us. First, we chose one mediocre candidate (Perdue) and one sub-mediocre candidate (Loeffler). Neither were very good, but both could have won absent a dumpster fire of idiocy.
Second, yes, they shouldn't have done mail-in balloting. Polling places haven't been shown to be likely places of transmission, and they could have had social distancing, mask requirements, and hand sanitation. Instead of voting by mail, they should have increased the number of polling places, expanded them, and kept them open later to keep lines from getting out of hand. As I've said many times, high voter turnout isn't a virtue nor is it inherently a sign of a strong democracy if those people aren't informed. There's a reason why the founding fathers weren't fans of universal suffrage. If you don't care enough about an election to show up, there's a very good chance you aren't very informed. Those who aren't informed are going to be more deferential to mainstream media and culture, and that's always going to favor Democrats. That's why Democrats like mail-in voting.
Third, if you're going to do mail-in voting, you have to adjust for it. More voters means a broader and less informed electorate. That means you need to broaden your appeal to win. You don't market Chardonnay wine the same way you market chewing tobacco, and Trump apologists will never understand this. Of course, Trump did broaden it in some ways by appealing to working class voters and black and Latino men. However, he significantly narrowed it with educated whites, and he didn't do it with bad policy as much as he did it with bad PR and branding. That means that in terms of policy, we gained nothing for our losses. We only gained the ability to say idiotic and juvenile things and generally be rhetorically sloppy. Ultimately that's why he lost Georgia in the first place. Basically we're letting Georgia and Arizona turn into Virginia and Colorado just so we can talk a bunch of **** and disregard principles.
Finally, instead of letting the general election be a wake-up call and a chance to readjust (which really could have meant just acting normal), we did everything we could do to compound the problem. We could have made Ossoff's and Warnock's nuttiness an issue (and there was plenty of material), but instead we peddled stupid conspiracy theories with idiots telling people to boycott the election, threatened people who didn't go along, and pitched flagrantly anti-democratic and crackpot ideas like invalidating electoral votes and even goofier, asking Pence to refuse to count certain votes. We did everything we could to look as nutty as we possibly could.
Lots of Republicans will put their emphasis on the mail-in voting, because it's an easy target and doesn't require any self-reflection. However, we won plenty of places that had mail-in voting. We could have done it and still won. However, you can't do mail-in voting and then do every stupid thing on the menu and expect to win. Normally a NFL team will beat a high school team, but if they decide to show up drunk, blindfolded, and handcuffed, that high school team will likely pull off an upset. That's basically what we did in the political realm.