Ah, I get to tell my heartbreak story......
I was in the same boat, 6' 180 lbs, RHP, sat 86-88 in college. Averaged 10+ K per 9 with a solid breaking ball. I was always a little wild (4-5 BB/9) which was a mark against me. Got alot of interest as a junior from the Reds and Pirates. Bill Bryk, Pirates scout calls me on draft day in 1995. I'm at my parents house for the summer and I'm actually sitting on the can. My mom says I have a phone call, I tell her to take a message, I'm busy and she says oh, no, you want to take this one. So I'm sitting on the can talking to Bryk and he tells me I'm on his list but he can't say how things will go and asks me if I'll sign for $1000. I told him I'd PAY him. Never got the next call, I saw him again before my senior year started and the consensus was I was a "smallish" righty.
Worked my ass off that offseason, thinking, I'll show them. Finished my senior season undefeated and broke a couple school records, but the scouts weren't coming any more and I wasn't totally sure why. That summer I went to a pre-draft tryout with the Diamondbacks, hitting 87 consistently with probably the best breaking ball of my life. Brad Vaughn, the scout running it, comes up to me after I'm done, says 3 things, first, you're looking to play somewhere aren't you? I said hell yeah, with heart pounding in my chest. Then he says I have one of the best breaking balls he's ever seen. Now my heart is really pounding in my chest. Then he asks, how old are you? I was 23......he said I was too old. I was devastated. Now I knew why the scouts weren't even looking at me. Smallish righty, past draft age. He made some calls for me and got me setup to play in Springfield Ill for an independent team but I was graduating in a couple weeks and had a job lined up, I didn't see much point in kicking around the independents for no money and little chance to make it.
What can you take from my story? The bias is real and for the most part they are right. Smallish righties without that plus velocity are common and they break down. 2 months after that DBacks tryout I tore my labrum and rotator cuff. Don't lose your dream and don't give up until the chances are all gone, but be realistic about it and keep that back up plan ready.