As a published author, I'm glad copyright existed. Without it, none of my publishers would have been in business and I would have had to find some other income source. But I think the default should be "public domain" rather than "copyright", and I'm skeptical of allowing corporations to own the copyright to individuals' works.
Do you think that those publishers would be significantly worse off if the copyright length was, say, 20-40 years rather than the 70 years used by most of the western world nowadays?
Well, most of my work was programming books, so honestly a 5 year copyright term would have been plenty. But the internet put most of those publishers out of business anyhow.
Outside of my own special case, I don't have really strong opinions on the term.