You need a separate page for each policy because the law says so.

Article 7 of General Data Protection Regulation (GDPR) provides that when the processing of data is based on the user giving consent, you must be able to show that the user agreed to the processing of the data. This means that if you are bundling all of the policies onto one page, you will not be able to show that the user agreed to the processing of their data because they agreed to like 50,000 other things. So the user can say “oh yes, I agreed to the Terms of Service, but not to the Privacy Policy.”

Also, GDPR requires you to present the request for consent in a manner that is “clearly distinguishable from other matters.” This means that if you bundle all of your policies into one place, a user will not be able to easily distinguish between all of your requests and thus you will infringe on GDPR. Here’s a screenshot of the actual text in case you don’t believe us.

You can read more about this topic on the great blog post "Should you consolidate all policies onto one page?" from the Termageddon team.