The situation follows the "mobile" (cellphone, tablet) situation where Chrome was just not providing an extension API that could be used to implement adblockers (or much else for that matter, e.g. Cookienukers).

This is no surprise at all. Competitive pressure for "desktop" (non-crippled computers incl. Laptops) required providing suitable extension APIs, but the writing was on the wall for a long time.

Some powerful people inside Google consider it theft to browse the web while blocking ads.