I have to disagree on this. Not requiring an email was a big reason I actually signed up and am active on here. Plenty of people do not want their email tied to their online activities and it simply adds another layer where they can be tracked. Email, in the end, is about as useless and cumbersome as requiring a phone number for everything. Bad actors will circumvent and only people who wish to contribute in good faith will be impeded.
We currently have captcha enabled on this server which is sufficient for bots and low-effort trolls. I believe time will bring more robust moderation tools and guidelines to deal with the pains of expansion. Right now, our efforts are better served towards accessibility of new users.