I have no use for LinkedIn generally (at least not now) but I've had an account for years with links to some old acquaintances I don't really care to be associa

I have no use for LinkedIn generally (at least not now) but I've had an account for years with links to some old acquaintances I don't really care to be associated with anymore, due to several industry, geographical, and social changes. I checked it on a whim about a year ago and found an old message from someone I hadn't talked to in over 7 years, very professional message just trying to catch up. I have no other social media accounts and am not easily found through general searches, so it was the only way this person could reach me. I felt horrible for weeks that I had never responded, then I sent off a reply. I then promptly forgot that I did so, and abandoned LinkedIn for another year. I checked again last week for some reason and I had a year-old response to my response. I forgot to reply and only just now remembered this situation. I'm now trying to decide if I should bother responding and risk another long delay, or pretend I'm dead.