Earlier quoted context omitted.
Requiring consent as a pre-condition of a service is frowned upon under GDPR. If you have a legitimate requirement (which is fairly rigidly defined under GDPR) or legal obligations for that data then you don’t need user consent, but if you don’t then you need to offer the service regardless of the user consent or not.
> Requiring consent as a pre-condition of a service is frowned upon under GDPR. No, it's not. Requiring extraneous consent as a precondition of service, that is, requiring consent for some processing as a precondition of provision of a service that does not depend on that processing is an indication that consent is coerced rather than freely given, and hence not effective consent, under the GDPR. But what that means…
Consent is only one of the six grounds for lawful data processing. Consent is not always necessary, nor is it always sufficient.