> Everyone on a free slack instance is NOT using a competitor's product.
Arguably this is even worse from slaks POV, no? Everyone on free slack is on free slack because they aren't willing/able to pay and slack would indirectly benefit if those customers were freeloading (and incuring costs) for their competitors.
Not the OP but I think if free slack becomse unattractive enough people might start to look around. There are enough alternatives (self-hosted like Mattermost, Rocket.Chat or free tiers from other vendors e.g. Zulip, Discord). That presumably has two effects:
1. People are used to them and if the decision at the workplace comes up to choose a solution the other product is on the table. Or worse if Slack messes something up with the paid tier people might be more willing to switch to something else that they know already.
2. Every private group chat might involve people who never used something like it before. For these people the software they use first is the baseline. And they are more likly to recommend the solution they already know to a organistation that is willing/able to pay for a higher tier.
We can't assume someone who won't pay for Slack won't pay for the thing they move to. How many people do you think pay for Discord's paid features that never would have paid for the forums Discord killed? The almost $15 billion dollar valuation suggest a lot.
Arguably this is even worse from slaks POV, no? Everyone on free slack is on free slack because they aren't willing/able to pay and slack would indirectly benefit if those customers were freeloading (and incuring costs) for their competitors.