Twenty per cent of ALL Paypal users in the US? I find that totally impossible to believe. I doubt 20% of them even know it's there, let alone have had a dabble. Paypal is something you mindlessly log into to buy something. Not many go much further or explore whatever else it offers.
I'd assume most users literally only use it when there's a "pay by paypal" button on a website, and therefore only log in, and pay for things. I'm not overly familiar with Paypal, and I haven't looked at this recent addition of cryptocurrency, and Paypal in depth. For US residents does it even advertise to existing customers that its been added? Like is there any pop up telling them its been added?