It definitely can be jarring. I say this as a resident leftist on this thread who openly supports not misgendering/deadnaming them. But there was definitely a point where I didn't know Lily was trans for up to like.. a full year after her transition? And I was still a fan of hers at the time, I just genuinely assumed she was a dude with a female avatar named 'Lily'. She made no real effort to try and portray herself as a woman in her videos until she like flat out said in a Q&A that she was trans and it finally clicked for me.
Mik is different because in my opinion her voice does sound genuinely a bit more effeminate than an average mans, but after seeing the video @
ÁchtunaRoll posted I can see there's no real difference between now and her pre-transition. Which is odd because Mik has stated she's doing vocal therapy to try and sound more feminine..
Still though I know what it's like to be a normal cis-woman with a deep voice and so I'm not exactly one to judge others on how masculine their voice may sound, as it's not entirely an accurate way of judging another persons identity. That being said, I don't think it's weird that their voices seem off putting, especially since they make no real attempts to come off as feminine in the first place.