Unless explicitly stated elsewhere, his webpage doesn't collect your data. That's it, plain and simple. There's a few other things I'm fairly sure I have to mention, though:

• This site is routed through Cloudflare, which has its own privacy policy that affects this website. Check it out here. I also use some files from CDNJS, which has the same policy.
• I host this website using GitLab Pages - go read their policy.
• Some pages have comments powered by Commento.io. You can check out their privacy policy at commento.io/privacy.
• Ash's custom Mastodon timeline pulls from an Atom feed running on my home instance, im-in.space. That instance shouldn't ever see your data, but if you're curious anyway, you can view their privacy policy here. The timeline does log your preference to load or not to load images, but this preference is stored in your browser. (I never see it.)

You can opt out of Commento services by disabling JavaScript for this website. There's not much I can do about Cloudflare, sorry.