Jonclegg.github.io is a GitHub Pages subdomain that currently serves up a 404 error page. That means the site either never had content or the repository behind it was removed or made private. For a personal blog or portfolio, the most common setup is a live landing page or at least an 'under construction' notice. A straight 404 is unusual and suggests the owner hasn't deployed anything here yet.
If you're wondering 'is jonclegg.github.io a scam' — there's no evidence of malicious intent, but there's also nothing to evaluate. A site that doesn't serve content can't host a scam, but it also can't provide what you're looking for. For a legitimate personal site, you'd expect at least a simple bio or project links. The absence of any visible information means you should treat this domain as inactive. There's no reason to visit unless the owner points you here with a working page in the future.
For now, jonclegg.github.io reviews are meaningless because there's no site to review. If this domain was advertised somewhere, ignore it until you see actual content. The infrastructure is clean, but a 404 is a dealbreaker for trust.