Bedrockgames
I post in the voice of Christopher Walken
But, that's the problem. It's a nonsensical question. The question that should be asked is, "Is this song by Robbie Williams a well written song, given what we have learned over the past thousand years or so of critical thinking analysing music and art?"
But musical conventions change. Modern pop music doesn't adhere to many of the structures, rules and conventions of Rennaissance or classical music. There are some rules of composition people adhere, but those can change dramatically over time. Just look at the difference in structure between jazz and baroque. And in music, breaking the rules is often quite okay. Roy Orbison didn't follow standard song structure from his time (not because he was intentionally flaunting convention, but becsuse he didn't have a handke on song structure). This led to some pretty memorable work. At the time, folks could have argued it was bad design, because that wasn't pop songs were supposed to be structured. Even the notes we use can change. Most western music had 12 tones, but arabic music has 24. For a while western composers experimented with 24 tones (and many still do). Scales and chord progressions also vary a lot by place and time.
That said, there would be some really odd musical choices one could make that I think most folks wiuld agree are bad unless you had a good reason to do so (things like changing time signature ever single bar). But those genuinely bad things are extreme cases, and eve some of those can change.