I think Linux has progressed a lot since 2005. It’s mostly idiot proof these days - it asks about language/keyboard/timezone/wifi and unless you ask for an advanced install (to partition a hard drive or whatever) it just installs.

I don’t think installing Windows is any harder but it may stop to ask for a registration key. Windows also prefers to connect to wifi during installation to fetch patches whereas Linux tends to do it after the fact.

Unless you’re installing some weird corporate build of Windows you’ll have a very simple installation process. Linux has caught up a lot to that experience.

Every operating system contributed to the bloat. Windows has Win32, OS X has Carbon / Cocoa, Linux has X11 and various widget libs that sit on top of it. So it has been a perennial nut to crack to make cross platform widgets - wxWidgets, QT, SWT/JWT/Swing on Java, XMLShell (Firefox), Electron, GTK/GTK#, winelib etc.

Throw mobile platforms into the mix and it’s an unholy mess. Lowest common denominator is HTML and so the likes of Electron “wins” even though it’s bloated and slow.