MONTREAL — MindGeek, the company behind some of the world’s biggest porn sites, has led a fractured existence over the last year. At this time last summer, it had a Big Tech reputation and a balance sheet to match. As with Google and Facebook, MindGeek was flourishing in the pandemic, sucking in and pumping out even more gigabytes for a locked-down audience of millions. There were hackathons for MindGeek employees and a small-business ad program for COVID-19-stricken businesses. Its corporate website, devoid of even oblique references to its core product, instead emphasized its SEO abilities and Big Data prowess.