The key of izumo is to resist the temptation of go all in and committed because your turrets are all front.
Though the ship's back armor is crapwhich will get tons of half damages from cruisers, not to say how easy is it set on fire. So there is a trade off to run away.
Also the ship is quite powerless in a tier 10 room, but tier 9 or below is in fact quite strong.
To summarize, the problem with izumo is that your joyful moments fluctuate too much due to various reason.
Therefore, you cant blame people losing confidence after trying it.