It would definitely could be a barrier to entry/onboarding.

I think for me I would want to see the “like” exist as a free option for all users, but with the ability to filter it from your notifications.

I have a lot of thoughts about how Bitcoin fights spam and why implementing costs isn’t always as bad thing. Hard for me to express fully w/o long paragraphs right now… which means I need a better understanding myself to be able to simply my thoughts.