It's part of the EU sanctions, EU ISPs are required to block certain Russian sites. But they didn't specify how, that's left up to the countries to figure out afaik. But as you say, some of the what has been done barely qualifies.

Here's my personal experience with this:

Germany does exactly what you describe, the bare minimum to say "we're blocking" --- DNS omitting certain sites.

Spain is doing deep packet inspection, blocking DNS requests that lookup RT, so DNS over HTTPS or through a VPN is a must. Additionally, they're also reading the SNI in TLS requests and blocking that way. If you try accessing RT in pure unencrypted HTTP you're get some fortigate blocking message back.