Assuming the cost is stupid low like a $1/year, low enough that almost nobody will think ‘is this really worth it?’-- every required click or tap after hitting ‘subscribe now’ costs you 25-50% of the people who are still there.
Make it 1 penny for a lifetime subscription. Just having to thumbprint for Google Pay will still cost you 25-50% of the people who hit subscribe. Make it a credit card form with card/exp/cvv/address/tel# and your purchase rate is down to maybe 1% of the people who hit subscribe.