How are people using canonical tag in 2026?

Same way as always really. Self-referencing canonical on every page you want indexed, filter and parameter versions pointing at the clean URL, and a cross-domain canonical if someone republishes your article. The thing people forget is that Google treats it as a hint, not an order. If your internal links, sitemap and redirects all point at a different version, Google will pick that one and ignore your tag. URL Inspection in Search Console shows the user-declared canonical next to the Google-selected one, so check a few pages there.