No, slack free plan only allows 10000 messages to be saved at any one time. Nothing to do with user limit.
Unbelievable that a service like this would change the key part of their platform without even checking the pricing page to see what free plan restrictions were...
Unbelievable that a service like this would change the key part of their platform without even checking the pricing page to see what free plan restrictions were...
https://slack.com/pricing
EDIT: I stopped reading after the first paragraph, looks like there was a user limit issue too :)