I wonder if it is easier to go without PMs where you have a focused product with a very specific type of users, often developers. In that case, your developers can more easily relate to the company's customers.
On the flip side, imagine a product that is used by accountants, doctors and other diverse users. I can see it being more difficult for devs to juggle coding and product management.
Yeah, Michael and Ben will still be maintaining Kickoff. There's some precedent here: before Saikat and Sheena joined Stripe about two years ago, they'd previously been working on Mockingbird (http://gomockingbird.com). Since then, they've kept the business up and running (on Stripe!). Given both that precedent and how much work Michael and Ben have put into Kickoff, we felt it made sense for them to keep it alive.
I'm sorry but last time I checked, Mockingbird development is all but stalled since the founders got hired by Stripe. Which is a shame, given how a great product it was.
Since you're probably gonna see them around, please ask them: why don't they just hire an employee to do actual work for Mockingbird? Thanks!
If I ever decide to work for someone else, I'd want to choose a decentralized place like those.