The market for collaboration tool has been sparked by Slack a few years ago. It has been subject to heavy fights since. Microsoft Teams not only entered the market but overtook the early mover quickly. The fight escalated perceivably when Slack accused Microsoft of ripping off its ads in late 2019.
AWS and Slack recently announced a partnership, indicating how hot the market apparently still is. With these two heavyweights in the ring, expect some movement in the space.
Source: The Verge