The Dems are getting blamed for high inflation. Again, this is a bit nonsensical

It's more than a bit nonsensical - it completely is - it's a global phenomenon, and Biden isn't in control of the entire world's economy. With gas prices: as you noted, despite the clear increase, the US has some of lowest prices in the G20. Beyond that Biden and the Dems are crippled from making any meaningful changes mostly thanks to Manchin and Sinema.

Dems tried to pass a price-gouging bill to limit oil company profiteering - the price per barrel on oil was $50 higher in 2010, but gas was dollar cheaper (adjusted for inflation) at the pump then. That's just one example, not to mention bills to cap costs on insulin or baby food which no republicans voted for. Gutting Social Security and Medicare (already pretty fucked currently) wouldn't solve any of this at all, and they know it.

The problem is: many US voters and especially "swing voters" don't consider macroeconomics or the bigger picture with Congress, the filibuster, etc. - they simply blame the party that holds the White House currently, as if the president can literally just issue an executive order to "stop inflation" or is a literal dictator, which depending on how things go in the next few years, especially if Republicans win the Senate, they might just get.