Fire your Marketing team
You have a good product, however, removing your lifetime product to use that money for engaging with creators is stupid and will lead to death of your product
First( and the ones that have a large lifetime account are going to hate me), is you should have never allowed stacking over a certain amount. Now they are costing you a lot and have probably already talked to the people they were going to organically tell.
Why would I recommend this product over a product like koofr that is still offering at least 1TB lifetime( it has vault) to a non power user.
Client side encryption is a value built over time(for the average person) and now no new customers are going to try it out. Because they have to buy a subscription to get it.
Preferably you should of just capped it earlier and created 1 lifetime tier at least until you were mainstream