Weaker than standard physical store consumer protections (no playtime restriction on returns, obviously), and (much) weaker than GOGs refund: 1 month after purchase, no playtime restriction.
I believe they explicitly called out the equivalent for physical stores and european consumer protection in general when they announced the policy and lack of restrictions. Which is an indirect call out at Steam, which hasn't cared in the slightest and continues to have a worse policy.