I work on something that would be a competitor to Level, so I'm sad to hear this, not only because of market viability, but also because I share the belief in Slack being anathema to any sort of focused work. There's a lot to unpack here, but briefly:

— The amount of effort, design expectation and polish everyone expects from a product is exponentially increasing. 'I'm one guy, Google is 75,000 people' is no longer a valid argument. Arguably it never was, but especially now you cannot ship a product that does not do what it says it will do to a very high degree. That effectively makes for longer product development processes and probably makes bootstrapped competitors to Slack unviable. At least, this was the logic I ended up going for institutional venture capital: it buys me the time to make it work.

— Non-real-time communication is useful when the team size grows above a certain point, however when that happens the companies grow and have higher expectations of their tools. So this market is an interesting one in that it largely forbids scrappy, just-alpha-don't-mind-me kind of products. Trying to sell to smaller (less than 5 people) startups will fail since they do not yet have a problem with Slack, and anything above, companies get increasingly desperate, however, the tool space rapidly diminishes as companies grow.

— This sort of non-real-time communication requires a lot of trust in other people in your company, in that they will see and eventually respond. In real-time, you can know if somebody hasn't responded in a few minutes. Your delay risk from a single question moves from a few minutes to a few hours, to a day, or larger if your team is distributed across the planet. It requires a certain type of team with this kind of trust to make it work. It's a cultural issue as much as a tools issue, and a good designer not only builds the tools to make things work, but also builds them in a way that they shape the team culture so that the tool can work. In our specific case, our main goal is to make your team a more trusting, more efficient one, not just to make you focus by reducing notifications spam.

— Derrick is a bit of a known person, with a podcast and all, and I think in this case it worked against him somewhat. He mentions receiving interest from his fans, this (fans of your personality) is an audience that converts especially poorly.

— Slack is a complex tool serving a variety of needs, so it is very hard to replace it without being Slack - and if you try that, you'll end up with just an inferior copy. However, what one can do is to handle a subset of tasks it does better than it. However, even this will take multiple years for a team that has no runway problems because of the expectation of polish mentioned above.

— "Everyone is lying", as a designer, I do take a bit of an issue with that: it's not that everyone is lying, but that everyone has different incentives. And when you're a known person, those incentives align with keeping you happy, so that you'd become their acquaintance for potential use in the future. This is not conscious, this is just human nature. This happens even when you are just a nice person that they don't know. Empathy from your users is a powerful thing. It is also your enemy.

They are not lying to you. They want you to be happy. I won't blame users for that. It is your (our / mine / other designers') job to counteract that.

I have a lot more, but I'll leave it here since this is already too long because I think about these all day every day. If you think this is interesting, though, happy to chat. (Email in my profile.) We're launching pilots in a few weeks. The core idea, I like to say, is that Slack is a marketer’s idea of what a good comms tool should be, while Aether Pro is an engineer’s.