You might not familiar with how the internet archive does the book lending. The book is actually drm-protected and can only be opened with adobe software, which will expire in just a few days, rendering the file useless. What the internet archive did was simply allowing more people to borrow the same book during pandemic instead of only allowing one person at a time. The lent books still expire after a few days. It’s not like the internet archive was suddenly turn into LibGen and distributing unlocked pdf to anyone.