Whether there is an afterlife or not would be important to me and to many other people.
Aside from that there are many things which are important to us which are not material - love, friendship, art, music, etc.
Music is not material? Is that an offer to lug, six blocks and up and down two flights of narrow stairs, my contrabass and amp and music stand and sheet music and cases of associated electronic gear to and from our next gig and pay for drycleaning the concert black clothes?
Would you be interested in an afterlife that was "non-material?" Some people seem to think of an afterlife as something ethereal, ephemeral, and non-substantial, but I think an, "afterlife," (which I guess ought to be called, after-death) existense needs to have some kind of materialness to it. Who wants to be a ghost?
Aside from that there are many things which are important to us which are not material - love, friendship, art, music, etc.
I know people say that, and it sounds sentimentally fine, but it is just not true. I want my friends to be real, material people that I can enjoy real material things with, like meals, or even conversation, sitting in material chairs and drinking material drinks.
The love of my life is quite material and I would not have her any other way. All of the things I do for her require material things, even the paper I write my love notes on.
What art is non-material? How does one produce music with non-material instruments. How does music (sound) get propagated through non-material space. If you listen to much music, as my wife and I do, there are material CDs played on a material stereo.
The sentiment you expressed is an impossible one. Without matter, all these values would be impossible.
Hank