"Toughness" comes from the alloy, the hardness, and the quality of heat treat. If you want edge holding plus some pretty high toughness at a reasonable hardness, M4 wins cutting contests. Carbon steel. If you want more toughness and still high edge holding, 4V and 3V have much to offer. Carbon steel. If you want indestructible, S5 and S7 are amazing. Carbon steel. Crucible provides plenty of charts that their engineers have made putting their excellent selection of carbon and SS up against each other for both toughness and edge holding.
You can make some stainless steels much tougher by running them relatively soft, but you lose the edge holding properties.
You can also take a fantastic steel, like A2, and HT to 58 Hrc and essentially destroy the toughness inherent in the alloy because you tempered it at 450° F and caused Tempered Marstenite Embrittlement. I'm starting to believe that this is actually so common in the knife industry that an awful lot of carbon steel knives are essentially brittle.
Beyond getting the HT right, Cold Steel used to advertise CarbonV as indestructible. When Camillus closed and the CarbonV dried up, that advertising changed. When you see broken carbon CS blades, is that because of the length of time CV was advertised, or because AUS8 is actually tougher? I would say it is the first.
As far as VG1 core steels, this isn't "stainless knife steel", this is a composite of high carbon VG1 and low carbon, soft structural steel. It should be better - it is a very costly, lower strength way of making a blade. The side steel encourages bending, not fractures, and it will bend with much less force than a fully hardened steel.
If you want to compare apples to apples, you have to start with steels being HT'd to the proper range for that steel. Consumer products aren't always the best place to judge this. But I would put an A2 blade tempered to 60 Hrc up against most any stainless you've tried for both wear resistance and toughness. 58 Hrc, not so much.