Ad blockers are essential for modern browsing, but they can occasionally prevent "legitimate" downloads from starting if the website detects the blocker or if the download script is mistaken for an ad.
Most websites rely on ad revenue to provide free content and downloads. When you block ads, they lose the ability to pay for the server bandwidth used for those downloads. Additionally, some download buttons are tied to tracking scripts or pop-up redirects that ad blockers view as "intrusive," causing the button to become unresponsive.
Instead of turning off your protection for the entire web, you can "whitelist" or pause it only for the site you are currently using.