@eskaigarcia Yes, I agree that Vivaldi is cluttered, very cluttered, but it can be customised to remove any menu items, toolbar buttons, speed dials, or panels that you never use. Its wide range of features is what makes it attractive, and there is a long list of over 5,000 feature requests, so at least some users clearly want more.
Out-of-date UI Design is highly subjective. Retro is often fashionable.
Try the Opera 9 Classic Theme for example.