All of those opposition parties banned have explicitly been in favor of Russia annexing Ukraine. Literally every one.
Not only that, you make it sound like he did this by himself. There has been a ton of parliamentary agreement and has also been upheld in numerous appeals (incl by judges not having any associations with Zelensky).
I’m by no means a “Zelensky-stan” and have my own criticisms, but either you are seriously being misled or are being malicious/spreading misinformation.
Not only that, Ukraine runs a parliamentary government. There is no “opposition party”. Americans for some reason always view foreign government political parties through the lens of American politics. This is not like the government banning Republicans. This is like banning the “Socialists for the release of Alaska to Russia” party.