IANAEUL (I Am Not An EU Lawyer), but if you're in Europe, that's definitely a GDPR violation. (If you aren't, then... you might not have any options, though some US states have relevant laws.)
The "if you consented, you may withdraw consent" seems likely to be a GDPR-oriented thing--there are rules for what kind of data collection does and does not require consent. They're probably leaning on one of the legal bases other than consent. See https://gdpr.eu/gdpr-consent-requirements/, subheader "The GDPR requires a legal basis for data processing".
no subject
The "if you consented, you may withdraw consent" seems likely to be a GDPR-oriented thing--there are rules for what kind of data collection does and does not require consent. They're probably leaning on one of the legal bases other than consent. See https://gdpr.eu/gdpr-consent-requirements/, subheader "The GDPR requires a legal basis for data processing".