Is progressive taxation fair?

Not really a Belgian related question, but something which has always baffled me

If I earn 100.000 EUR a year why do I have to pay a higher % of tax than somebody who earns 50.000 EUR a year.

Say I have to pay 60% in tax, so I return 60.000 EUR to the taxman - my neighbour has to pay 45% so he returns 22.500 EUR in tax. If I had paid the same %in tax as my neighbor(45%) I would still pay almost 2 times as much in tax. Why am I being punished relatively speaking when I already pay more tax and how can it be fair that I have to pay almost 2 times as much in tax just because I earn more

This is a thing which has always baffled me, I am curious why there are some people who think that apparently it is only fair for people earning more that I have to pay a higher % when I already pay more in tax than my poorer counterpart - to me this seems blatantly unfair to me. I am really curious to hear why this viewpoint is so entrenched and never questioned