The guys who get the short end of the stick on this are the guys who are stuck in an endless cycle of "one date, no sex, no second date" type interactions. They put in most of the effort and never get rewarded with the era where a woman starts to put in some of the relational effort.
That was basically my life from 2016 through 2019, which was when I totally gave up and moved on to other things for the sake of my mental health. Nothing was working and I legitimately thought I was developing some mental health issues (extreme anger, constantly second guessing myself, developing body image issues, etc.). Crazy part I was even going for women below my actual league and got nothing but attitude but yet these women would go for literally obese men, guys a full foot shorter than me, etc.
Too many "one date, no sex, no second date" type interactions with 0 successes will be psychologically traumatic. I'm not surprised that you experienced any of the things you experienced between 2016 and 2019 with those "one date, no sex, no second date" interactions.
Never go for women beneath your league. Since you are 6'4" and you have big muscles, your league is an impressive league. You need to only interact with the fittest women. The height thing is a huge advantage. Taller women, who have a smaller market, could really be into that. You could seriously consider focusing in on 5'10"-6'2" women. These women don't have as much of a market since they are either the same height or taller than a lot of men. You are meaningfully taller than the 5'10"-6'1" women. I could imagine a woman in that height range being quite attracted to you conceptually.
You might now even be rich enough to play the "rich older guy" card with some volleyball players/swimmers at the major university near where you live. An 18-19 year 5'11"-6'1" volleyball player could get into that. You could carve that persona.
You could also find some ex-college athlete gals who have stayed fit and possibly obtained breast implants post college.
You've got a great league. Enjoy it!
A good portion of the reason you were treated like shiit earlier is because you were dealing with shiit quality women and weren't selective enough in your overall strategy and you didn't use the right tactics to put the strategy into practice.
As
@BackInTheGame78 mentioned, I think the only way to really tell if a woman is interested is if you've had a sexual experience with her AND she is still in contact with you. Even something like her having sex with you doesn't mean anything, I've heard stories of women going all the way after a first date and then the hamster wheel spins with thoughts like "I just had sex with him on the first date, he'll just think I'm easy and just want me for that and not want anything more, I'm so embarrassed.".
Yes, this is a good point and it can happen.
I learned a while ago to stop stressing myself out over stuff like this and unless a woman is actively going out of her way to pursue me I don't bother and put 0 effort in.
Few men have that luxury but you do. When a man is 6'4" and big muscles, there's a lot of potential for women to actively chase him.
You have sent a follow-up message, and she has your number, so everything is up to her. In the meantime, SPIN MORE PLATES.