Meh, not really. This has always been a majority-liberal board, and it has always had a high percentage of liberals being aggressively condemnatory and/or condescending about various anathemas of right-wing behavior. A hell of a lot of vitriol has been dumped on these boards in the past about, e.g., the Iraq War and Bush Administration economics and conservative climate science denialism and a mass of other right-wingery. Conservative Dopers of the period gleefully wallowed in that “hostile environment” because they thought they had arguments worth making.
The main difference between then and now is not that liberalism has been getting more censorious, but that conservatism have been getting less and less defensible. Conservative Dopers used to find it easier to believe that they had a cause worth fighting for, in the form of pea-knacky “democracy promotion”, Gingrichian “small government” ideology, market fundamentalism, complaints about “liberal media”, “climate skepticism”, and a host of other positions that still had some amount of mainstream intellectual respectability even if liberals in general despised them.
Now, though, in the Age of Trump…
with conservative media largely mired in “alternative facts” and straight-up disinformation propaganda,
with the Republican Party committed to a platformless program of sheer obstructionism and roiled with internal convulsions about Trumpism,
with the conservative movement ever more entangled with low-information zany conspiracy theories and outright white supremacism,
with conservative “freedoms” ideology horrendously stained by its childish rebellions against sensible public-health precautions in the midst of a pandemic and the consequent hundreds of thousands of excess deaths,
with conservative economics producing ever more economic inequality along with insecurity, stagnation and “despair epidemics” among the non-wealthy,
with “climate skepticism” dead as the passenger pigeon,
with conservative ideals of governance reduced to the openly transactional buffoonery of a semi-literate reality-TV conman,
with the US’s “democracy promotion” wars leaving an ongoing shambles that voters turn away from in disgust,
with Republican anti-democracy policies of voter suppression and minoritarian power coming further and further out of the shadows up to and including an actual insurrection attempt in order to block or disrupt a peaceful transfer of power…
…well, non-insane conservatives are finding less and less about their movement’s current historical moment that can plausibly be defended against liberal vitriol.
It’s still possible around here to have the occasional rational argument with reasonable intelligent conservatives about some specific political issue on which reasonable people can disagree. But when it comes to standing up for “the right” as an overall political philosophy, conservative Dopers these days are mostly reduced to sullen silence or skulking around whining about how hateful and mean the libs are being to them and help help they’re being repressed.
It’s not that liberals have actually become nastier or more aggressive. It’s that conservatives in general have become more openly, obviously contemptible.