This is often overlooked and it's a fair point in defence of the people working for Yandex. You can't judge someone just for working for Yandex or even most Russian companies. The people who have voiced concern are already out of the company and it's perfectly reasonable that the rest would like to keep their jobs, especially in uncertain economic times with all these sanctions against Russia.

However, this also implies that Yandex, as a company, cannot be trusted. It's not the researcher's fault, but they simply aren't allowed to work in a way that doesn't reinforced the Russian government's bias. As usual, the Russian government is the real villain here, but its authoritarian rule "infects" any company and country it has control over.

It can be assumed that the people working for Yandex are also victims of their abusive government, but that doesn't change the fact that their work is unlikely to be trusted outside the Russian sphere of influence.