"Consent means giving people genuine choice and control over how you use their data. If the individual has no real choice, consent is not freely given and it will be invalid." and "This means people must be able to refuse consent without detriment, and must be able to withdraw consent easily at any time. It also means consent should be unbundled from other terms and conditions (including giving separate granular consent options for different types of processing) wherever possible." (ICO commentary)
Of course, this only applies wherever the GDPR applies.
https://ico.org.uk/for-organisations/guide-to-data-protectio...
Organizations can have a legitimate interest to process data in order to provide a user with the data service they signed up for.