I didn't watch his last stream in full. I can be pretty sure it wasn't other GMs being friendly and not wanting "free rating." What time control was the challenge?
Lower rated players don't experience what I'm about to share because chess.com is such a large chess site with many millions of members, but the elite players like Danya have such a high rating that there aren't many people in the world for the system to pair them against. If your speed chess rating is over 3000 like Danya's and you have your challenge seek parameters for plus or minus 200 points (hypothetically), then not many are higher and the lower end is still about 3000 rating. How many 3000 rated players are there even in the world? You can request a challenge seek, but the chances of these top players being online and not coaching, or creating YouTube videos or whatever else etc. is pretty low, so it's surprisingly difficult to find opponents. That's why you'll see top players constantly rematch against each other and often agree to play a certain number of games; it's simply not worth the wait to look for new opponents.
The most popular time control on chess.com is 10 minute chess. You won't see many titled players playing 10 minute chess though. Somewhere between maybe 2200 and 2400 is where most titled players sit. Maybe 2500 for GMs. It's not that higher isn't possible; it's just not worth the long wait to find a challenge. Waiting for one game might take as long as the game itself (20 minute wait in the case of a 10 minute game). A lesser extent this is why not that many GMs play 5 minute blitz. You have to go where the games are and most GMs play 3+0 blitz because there's more people at the top playing that. Same with bullet. I have some chess.com friends in the 2000-2400 range who report similarly long waits. I don't really have this problem too often, but I'll occasionally have a wait (finding a 10 minute game) of several seconds to a minute, but it becomes a longer wait the higher you get.
Alternative explanation why they may abort against Danya... they know how good he is and are intimidated to risk losing their rating to him. 
For starters RIP. What a great human. It's weird feeling like you know someone you never met just by watching their streams but he really talked to us low rated players and took time to explain and interact and it's hard not to care about a guy like that. Anyhow my question is, on that last stream I noticed a bunch of people were abandoning the game when they were paired with him. Even big names like Hans. And this appeared to bother him. Why were all these GM's aborting the game with him? Is the GM community so close that word got around he was tilting ELO and they were just not willing to take advantage? I found that really bizarre, like I'm sure they're not sitting around watching his stream. Anyone got insight to this?