It seems like I've been feeding a troll this whole time. I just went through the whole podcast /u/politicalanalysis ("political analysis" pfft) linked and they don't mention what this user has claimed. But I'm just replying for anyone that reads this conversation that would like to be informed. I have blocked and reported this user.
it does essentially eliminate all social safety nets
UBI itself is a social safety net. As I mentioned before, it's more flexible than any existing social welfare because it's direct cash.
Disability insurance is still purchasable through non-government means with cash you receive from the government, and current disability welfare isn't enough to retire either, so your argument is irrelevant to UBI -- a separate issue.