If the question is really “is it ok?,” I say of course it is. Your service, your email, you can do as you like.
If the question is whether you should do it, or how it would be perceived, those are different. If in my Delta Skymiles update emails they started throwing in the CEOs personal views on race relations or these issues, I’d find it weird. Maybe unprofessional? I can’t imagine sending my clients emails with my personal views on this stuff. It’s a great thing for me to maybe post on my Facebook to my friends and family if I want to. But as a professional message, it’s really not Delta’s place, or my place to tell people how I feel. So I think it depends on what you’re going for. If you intend for this to be perceived as an extended Facebook for you, that’s how it may be perceived. If you intend for it to be professional-level communication, it may seem weird. I’ve met you and know you through here for years, so I’m not offended or anything, and I think it’s fine. But I could hear someone thinking “great, fantasy football guy is now the authority on race relations and telling me what he thinks about it.” Just like if my barber or Ace Hardware or someone else told me their views.
In sum: Everyone I know on FB is taking the opportunity to share their views on this (some annoyingly so). I’ve not received nor sent a professional level communication on it.
Just my quick thoughts. Somewhat baked at least because I was thinking about this today in the context of my professional twitter feed. But I don’t have the answers on this.