> Are there no warranties that are required by law, not even in EU countries?

Warranties are consumer protection law, so don't apply if there is no sale from business->consumer. Since you don't buy OSS it's not an issue (just like the CRA isn't activated either). In B2B transactions, not even statutory warranties apply by default (generally, see local law). This trips up small businesses sometimes.

Warranties on software have always been a bit slippery, since it is licensed rather than bought. Hence why the CRA and the Digital Services Act had to be created to deal with these cases.