That's a possible interpretation. We don't hear the discussion before it. And it's a weird wording to merely offer a sale of assets for Reddit to then manage.
The word choice, to my ears, more implies a "just gimme cash to make me shut up & disappear" attitude, or at least openness to torpedoing every other goal as long as the cash prize is big enough.
I further think Selig's rush to qualify it as "mostly a joke" is evidence that he noticed, in the moment, that what he just said sounded a bit brutally grubby. Maybe by this point he was getting angry his other hints that he mainly wanted an attractive buyout weren't being met by serious offers.
As I mentioned, such a tactic could be far from what the law declares as actionable 'blackmail' but still feel like a tough, "play ball or else" shakedown on the other side of the negotiation – the sort of thing people commonly describe, though somewhat figuratively/hyperbolically, as 'blackmail'.
Is there anything "wrong" with that style of making joking payoff offers to "skip off into the sunset"? Well, in negotiations, as long as you're not breaking the law or sabotaging your longer-run reputation, what's 'right' is largely what gets you what you want, both for now and in enduring relationships.
Did Selig get what he wanted? Does he come off as a desirable & trustworthy counterparty in other future collaborations & negotiations?
I think he's got a legitimate beef with Reddit in many dimensions, but at the same time this audio clip doesn't make him seem super clear & fair in his communications.