Issues with home charging comes to mind, but I suspect it might have to do with gas station experience in Japan not being so miserable.

Phrases that are equivalent to "full tank every morning with no need for drives to gas pumps" basically don't appear on Japanese Internet. I just googled a bit for Model 3 user reviews in Japanese, and most mentioned items seem to be futuristic experience, various minor QoL and reliability issues like sensors and actuator issues, and disappointing chassis dynamics such as torsional rigidity and suspension designs. Few mention home charging and none as a positive. Fewer mention the CEO as a factor, whose eccentricity is still not widely reported in Japan - Trump/Musk derangement is not fun to watch and media tend to sanewash or simply skip over those.

Though, I think Tesla is also not doing that bad in Japan? I see pre-Highlander M3 and occasional MY Juniper on the road, about as often as Porsche(all models). It's slightly more common than Nissan Sakura, and definitely more common than Ferrari and BYD cars(all models).

Probably a mix between oil-ties and the fact that decisions in Japan are made slowly.

Edit: I also think there's a fear of this: wide acceptance of EVs open the door to BYD (or similar) huge takeover of the car market.

I have a theory: Japanese car's have excellent reliability, their interiors and design are lacking. If every car in the world is an EV, which due to their relative simplicity tend to be reliable, what remaining unique selling points does eg a toyota have?