From my small sample size, what I've seen online are definitely a younger set of fans. And let's face it...the show is flashy and sci-fi. A much needed commodity with a built-in fanbase of existing Trek fans.
The podcast place I refer to is full of two types of fans and I can pretty much nail their age within one or two posts Some older fans like us, let's say 35-60 and then the rest.
I got into a shitshow of an argument after I leveled a few critiques about a season one episode. The person started with - 'Oh so you're one of the haters because it's new and you don't understand it...'
How do you even begin to respond to something like that? Well I did and it began with - Yes I am a hater of the events I've brought up here and you don't seem to think that's allowed. Are you going to tell me what my favorite color is next? Or that my opinion is not allowed here because it differs from yours? I really lean on the ideas that it's entertainment and the internet allows us the ability to have varying opinions.
I can tell by the failures in answering my questions and their pathetic attempts at telling me what 'I should be thinking', that the person on the other side of the convo isn't over 25. And yes a large part of that demographic often falls back to the - You don't like Discovery because the main character is a strong woman! Oh boy did I ever respond to that POS and let him/her know the reasons I can hate a character without ever alluding to gender or color