What is going on with these mixed signals?

A guy I used to work with and I were super close. We know each other better than we know ourselves, he said I'm his best friend, and that I'm like family. Work was spent laughing our heads off, with him always doing dumb stuff to make me laugh. I miss it. He truly was/is one of my best friends.

We're both commitment phobes, so I'm not wanting anything serious. I'd asked him to hang out twice while we worked together, but he said he wasn't comfortable with anyone at work, not just me. I accepted that, didn't push, and wasn't really even bothered.

Plenty of times at work where we definitely had a moment. He'd always back pedal though, and be distant for a day or so after. He walked me to my car with an umbrella one day. Definite moment. You can bet he did not walk me the next time.

He hung out with another coworker as he was leaving, but it was once and they hadn't been able to say bye. We had a sweet goodbye, he basically said he hoped to stay in my life, etc. I saw him a few weeks later, he RAN to me. The next couple times I saw him, he was stressed and just in an antisocial mood, but don't think his it was personal because he'd been moving and had a lot of life adjustments. Two weeks ago, I saw him at an event, and he was happy to see me. It'd been like a month and a half. He gave me a hug, and we chatted for a few minutes. I said I missed him, I got a very enthusiastic "I miss YOU." I said we should catch up sometime, and he was like "YES!" That yes lasted for about 15 seconds before he switched it to a, "Well, maybe. With our busy schedules." I don't like to put up with bull. I accepted his no before. I thought things had maybe changed since we don't work together anymore. I'd rather he straight up would say he didn't want to. I was like, "we don't have to if you don't want to..." and he said it was just that we're both busy. We really are. Lots of work hours, and are introverted and don't generally have social energy left. I get that. I just don't understand why he'd back pedal. Giving useless hope isn't good, but he generally means the first thing that pops out. He told me that if I reached out, he'd respond, and that was that.

Here's the other kicker- I reached out. He did in fact not reply. I sent him a brief messgae, and an old photo I found. It took him three dang days to even read it. Not sure when he would've if I hadn't seen him, and been like, "oh, by the way, I sent you this pic." He seemed happy about it though, and apologized, saying he had like 50 unread notifications. I believe it. He'll be super intentional if it's in person or important, but he's never been a texter. But the fact that he basically said to reach out and then didn't even open it for a few days? When he did respond, he reacted with a heart emoji to the text, and a laughing emoji to the photo, plus a brief message. The mixed signals are off the wall though

I generally think he's too honest of a person to actually have issues with me without saying something. An example would be me complaining about a bad hair day, and instead of "don't worry about it" or "it's fine," he said he hopes I figure it out. He genuinely was trying to encourage me without lying about it looking good. We've been buds for like two and a half years. He's initiated all the hugs, started the sweet convos, plays around with me equally, etc. I have been snapped at when no one else has been, but everyone who witnessed it just thinks it's because we we're close.

I have trust issues and have been burned in similar situations, but I'd like to think we're genuinely friends. So what in the mixed signals is going on? If he cares about me as much as he says, why doesn't he want to hang out, and why won't he reach out? Is it a, afraid of messing up our friendship type thing? I feel like if we opened the door, we'd go the distance. Do you think it could be an afraid of a relationship but also afraid of losing the friendship if we didn't make it? I'm just so confused. You can't fake some of this, he clearly cares. I feel like if he was just trying to be nice, he didn't have to say some of the things he's said, but he's been so distant.