I wish that Microsoft Outlook had a way to decline a meeting invite, but that would still keep it in my calendar.
I don’t want to set expectations that I will attend, but I want to keep the meeting invite so that I can see the agenda for the meeting. Often the meeting invite has information not covered by any other emails, and I want to keep that record (or as a way of keeping a note of when the meeting was scheduled). I often use “Tentative”, but I don’t want anyone to mistakenly assume I might attend the meeting.