I've been using Haskell for 20 years. I've been running a company built on Haskell for 10. I have a very large legacy Haskell codebase. I've invested in several companies built on Haskell. Your anecdote is about your own lack of familiarity, nothing more.
Yes, companies can get into trouble with Haskell compile times, memory use, etc., but enforcing disciplined coding rules and advances in tooling solved the majority of the problems by 2016.
We use LLMs to assist in writing Haskell and have for several years. We keep track of compile times to catch regressions and on our largest code base an agent-driven change takes an average of 96 seconds (as of this month) to compile. Agents looking to do quick compile checks during code writing can run with flags that make the compilation run in less than 5 seconds. In all cases, running out test suites takes a lot longer than compile times.
The only time this isn't true is when you compile from cold start, as you would when using multiple work trees...which is the expected behavior when vibe coding features. So yes, I believe the issues they're running into have a lot to do with vibe coding. Check out all their integrations...Haskell's probably a poor match for what they do, but vibe coding integrations is probably what they need to do to get new customers.