Something like "Twitter lied, actually 15% of active users are bots, not < 5%" would never count. But "Twitter lied, 85% of active users are bots, the advertisers found out, they stopped buying ads, and now Twitter has been faking revenue numbers to cover it up" would count.
It's hard to stress enough just how far Musk is from showing a Material Adverse Event, even if his wildest suspicions about the number of bots on Twitter are true (...not that it seems likely they are, mind you).
Edit: Typos.
The true magnitude of the bot problem is exposed in court. Twitter is exposed for not only lying to Musk, they're also now in trouble for lying to the SEC (for years) and by that same token, lying to investors and advertisers.
Twitter stock crashes to an unthinkable low, DWAC buys it all up.
Musk never intended to buy Twitter. The objective was to expose Twitter as the propaganda machine it is.
It’s like buying a house after famously visiting it every day for several years running, seeing all the faults with your own eyes, telling everyone you were going to fix the faults, and even trying to humiliate the sellers for not having built the house to your standards in the first place.
Edit: typos
The number of bots on Twitter has always seemed like a boon of an issue to me. Twitter wants to keep it's user/engagement numbers up and bots do help them. I can 100% understand why they've taken a soft approach to it, even if I find it ethically questionable.
I'm going to go out on a limb and say that anyone who's engaged with Twitter, or knows a reasonable amount about it has known about this problem for many years. I find it hard to believe that Elon wouldn't have been well aware of this upfront.
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The part of your simplification that I take issue with is, "[...] that the seller had hidden." IMO - everyone in town knows that house has building code issues, but, no one really knows the exact extent. Unfortunately, these same building code issues are likely keeping the building standing.
The seller has a gray-area "issue" that is on the fence between "feature" and "bug," and the buyer is using it as leverage to pull out of a deal they're on the hook for.