I doubt Mullvad would be doing this if they weren't getting compensated given they've always said (even right now[1]) they don't offer a free tier since they don't believe it makes sense.

The other aspect is I expect it would stain the IP pool further. VPN IPs often end up on various blacklists due to abuse and introducing a wave of free users would only make it worse for paying customers.

[1] https://mullvad.net/en/pricing

> Why no free plan? "Free" services nearly always come at some cost, whether that be the time you spend watching an intro ad, the collection of your data, or by limiting the functionality of the service. We don't operate that way – at all.