Because in the end its always all about the economy (not calling you such, I'm using the idiom here) stupid. Unless its a threat right on their doorstep, plebs rarely care about foreign policy while 90% of the time their wallets are on their mind. And if politicians can't deliver on that front, they lose their jobs no matter what kind of foreign policy boogeymen they drum up.
You're not arguing in good faith here. Germany's car industry was brought to a standstill and they practically begged on their knees to the Netherlands to hand Nexperia back to China, which they did. China won that standoff. Or do you think the only acceptable retaliation would've been to send a PLA brigade to Donbass?
Marcos played chicken with the Chinese coast guard, but rather than being a hero he's now staring down a 33% approval rating and hundreds of thousands of protesters demanding his government's resignation over corruption.
If your hypothesis is that Japan saw Nexperia as a lesson of how it can cross China's redlines, then I don't know what the cause for doomerism is because if anything it says Japan's leaders are so blinded by pride, (or I guess in Takaichi's case her Gaara levels of insomnia) they're unaware of how that episode ended and how it'll end for Japan once China applies all pressure points on their economy, which previously contracted 1.8% mind you.
If the US had a Democrat president willing to prop up Japan's econonomy that's one thing, but tariff Trump? Wrong time to be acting this bellicose.