I think their argument is that the tax revenue is still owed, whether it’s collected or not. So the IRS could absolutely get back on track post Trump and pursue these unpaid taxes.

It’s also a lightning rod issue that turns more voters away than it attracts.

Sure there are staunch anti-gun people under the Democrats’ tent but they’re not the kind of people who will vote Republican if the party suddenly scaled back or ended its decades long futile efforts at gun bans.

On the other hand there are a ton of white working class voters on the suburban-rural fringes of swing states who would absolutely at least consider a Democrat if the party wasn’t so easily cast as “gun grabbers and job killers who only care about minorities”.

You get a pro-union, pro-legal-gun Democrat on a ticket who speaks on issues affecting rural whites as much as they do urban non-white voters (who are equally important), and you’d have a winner in many of these areas where they’ve been quite red, but not so rabidly Trumpy as other areas.

Even moreso if that’s a change that happened at the party/platform level.

I feel like from a campaign strategy standpoint, guns are just a lose-lose for the Democratic party. Playing to a base that would be loyal anyway for other reasons, even if the party dropped that position completely (which would not only eliminate a deal breaker issue for rural Democrats but also eliminate a cornerstone of the GOP platform in “protecting the second amendment”). Unless they did a complete about face and suddenly became as cozy with the NRA as Republicans, anti-gun voters might be upset, but they’re still voting blue.

After all there’s still abortion, electoral reform, racial justice, the environment, education, foreign policy, infrastructure, legal weed, LGBT rights, healthcare, and a host of other issues where the Dems are still their people.