It makes sense to sell if Slack will have more value as part of a larger company, compared to being by itself. Acquisition typically makes it easier to integrat

It makes sense to sell if Slack will have more value as part of a larger company, compared to being by itself. Acquisition typically makes it easier to integrate into that company's offerings, at the expense of making it harder to maintain all of the independent integrations that were in Slack's interest when it was independent. It makes a lot of sense for Amazon to offer some kind of managed corporate communications platform to customers who are already heavily invested in AWS, but in the long term, it would probably hurt Slack's core integration strengths. What would probably be best for Slack is to build out an on-premises enterprise version, which could then be deployed on your cloud of choice. It gets Slack most of the benefits of acquisition by a cloud provider, without the downsides.