Given that we base inflation numbers on CPI, inflation exactly is companies raising prices -- well, companies that produce the goods that are included in CPI, anyway.
Yes, we still have to consider the reasoning behind why they are raising prices. Personally, I believe it is more because of supply chain shortages than COVID fiscal policy (though the latter certainly contributes), but I agree that's up for debate.
Why?
Going by what I see as an individual, there are lots of things happening around me that drive prices up that don't have any strong relationship to my government's policy (e.g. bird flu raising poultry prices). I also don't understand how this can be the case simultaneously across multiple governments around the world.