Numbers yes, when you last contacted no. Core value prop of personal CRM is ease of keeping up w/ people, which means smarts of reprioritizing people based on several factors sort of like a personal assistant would, which means system should know when you last spoke/texted/emailed/etc. Ideally it'd even have ease of access to transcripts (chat/email logs) so you could jog your memory.

The goal is to avoid just a dumb timer saying 'its been 4 weeks, why don't you chat with X'. That's how Socialfly worked, and it was pretty high friction in practical use.