I think “underpowered” is a variable. What is “underpowered” to one person might be too much power to another. I own a 140bhp tuned car in India and when I moved to America and got my first car, it had more than twice the power of the car I had in India. I told my friends about it and they were like “That’s way too much power!”. To someone who owns M3s or M5s, the same car will feel grossly underpowered.
Also, like someone else mentioned. One can hardly utilize the full potential of a 250bhp car on the roads here. I can’t imagine driving a 600+ bhp car in the same setting. I’d be extremely frustrated on the highway, being forced to do 75-80mph, barely feathering the throttle and resisting the urge to floor it. But does that mean I don’t want more power? Hell no. There’s never enough power
Also yes. The 330i is a lovely car for what it is. When I first got it, I was sad letting my B9 A4 go and regretted getting the G20. But I’ve grown to love it and now, I have no regrets getting it. Well. One regret. That it isn’t an M340i.