I would say that Comodo is quite shady, sadly it seems that cloudflare sites use it so getting rid of it would be quite difficult.

They make multiple low quality and mostly useless applications - one could even call them scamware: https://en.wikipedia.org/wiki/Comodo_Group#Consumer_Security.... They also forked Chromium and Firefox and made their own rebranded browsers which offer nothing of value.

They have multiple clearly fake comments on their certificate pages: https://ssl.comodo.com/comodo-ssl-certificate.php and https://ssl.comodo.com/wildcard-ssl-certificates.php

And finally they tried to trademark the name of LE: https://en.wikipedia.org/wiki/Comodo_Group#Let.27s_Encrypt_t...