Wasn't she losing to Proxima Midnight + Corvus Glaive?
I believe she is getting stronger as she gets emotional, similar to Hulk in a different way, she also vaporized Ultron sentries when she felt Quicksilver died, she was probably amped when she fought Base Thanos due to Thanos killing Vision. In normal circumstances I believe she would lose to Thanos without even the Infinity Stones, considering she was losing to Proxima + Corvus, which Thanos one-shots them.
But if she is rage amped, I agree Thanos needs infinity stones to beat her.