I mean, 90% of employees on the UK(I imagine it's probably 99%) don't ever have to file any taxes - it's all done automatically through PAYE. Only in certain specific circumstances you need to file a self assessment. So yes, I sympathise with the administrative burden for UK businesses, but for employees the system is basically better than almost anywhere else in the world.
Why are people down-voting this?
It's generally correct: If you're self-employed / sole trader and operating outside IR-35, there's no way the HMRC can know how much you were paid as they don't have the info, so they can't know how much tax you owe.
In other situations for payrole / salary (like PAYE for example) they do have the info, as companies have to submit it, so generally people in those situations don't have to submit tax returns (unless they have significant capital gains).
I do think it's a bit annoying you have to declare tax on interest since 2016 if it's over £1000 - previously banks would take it out automatically, and this is still done in other countries (NZ for example).
Don’t let facts get in the way of a good narrative it seems.