Basically this. Some measure of gatekeeping & tard-wrangling (to use latter-day Internet parlance) is necessary if you want to ensure the integrity of any organization, and anything resembling an organized right would be no exception. It's not even a 'worrying about what the left thinks' deal or 'optics cucking' or anything like that, it's a question of not coming across as a completely unserious clown show that nobody in their right mind would vote for (which, yes, you do have to worry about if you aren't a reactionary terror cell actively plotting to overthrow the government rather than trying to play within the system in any way). As with political extremists in general, those on the right also tend to have spent a lot of time in political hugboxes where their views aren't rigorously challenged nor does anyone complain when they crack an off-color joke they'd never be able to get away with in normal RL company (not their fault usually, this was always how the Internet worked to a degree but the number of spaces where you can freely express right-of-center views has been dropping like flies), so they then think they can behave the same way as a public figure seeking office - invariably with disastrous results.
For one example, you can take a look at what happened to the UKIP after they let Sargon of Akkad in: instead of getting to discuss any serious issues they ended up wasting a ridiculous amount of time defending his casual jokes about raping Labour MP Jess Philips (which he quadrupled down on), which whatever you think about Philips personally or Labour & women generally, is not exactly the kind of thing that normie voters will laugh about or vote for. The result, of course, is that Nigel Farage quit to found a new party where such idiocy wouldn't fly and the UKIP was destroyed in short order. Or, indeed, the trainwreck that was YE24. Normies do not, in fact, enjoy it when you spout /pol/ talking points IRL, and they enjoy it even less when you associate yourself with absolute degenerates like Milo and Fuentes (people with huge Kiwifarms threads or an entire subforum in the latter's case, so it's not like those of a more rightward bent don't find them insufferable either) while still supposedly claiming to represent tradition, faith and fatherland. How exactly is one supposed to persuasively argue in favor of any of those things while having a white-nationalist catboy enthusiast who's been caught on camera throwing temper tantrums in restaurants as a lieutenant?
Not coincidentally, the left had to play by the same rules to get as far as they have. As a counter-example to the above, the gay rights crowd had to firmly and in no uncertain terms dissociate from NAMBLA and its ilk in the 90s in order to deny the right the ability to easily and accurately accuse them of being pedophiles or, at 'best', pedo-adjacent (which would have been absolutely true had they not done so). It's also absolutely not a coincidence that the idea of civil unions, gay marriage, etc. started gaining mainstream acceptability only after that point. Does anyone really think the push for gay marriage could have happened if the albatross of literal overt pedophiles had been something those guys embraced, rather than ran away screaming from?