I watched a lot of her videos a while ago. The things that really stuck out for me were:
1. At a young age, she noticed that her male friends could take their shirts off when they got hot outside, but she couldn't. This is something she states as "proof" she was meant to be a man. Instead of, you know, proof that gender roles aren't always fair.
2. She has not done much research on bottom surgery. In one video, she talks about how the hospital asked her to rank the goals of her bottom surgery: Looks, feel, and functionality. She said that she told the doctor her biggest concern was that it looks as real as possible, while feeling and functionality are secondary concerns. She then goes on to talk about how the surgery is performed, and then says "Actually, I don't really know the specifics, and I don't want to know, I just want a dick." This woman is about to have major life changing surgery, and yet she doesn't want to know more about it and do proper research before making such a huge decision. She's going to be in for an absolute shock whenever she finally has the surgery.
Kalvin is clearly a butch lesbian, and despite being on T for years, she still looks unmistakably female. Kalvin and other FTMs can kind of look like teenage boys when they're really young, but by the time they're adults, most of them just look like dykes. I forget the other popular FTM on youtube right now, but she also looked like a boy when she was young, yet now she just looks like a doughy woman with short hair.