Modern Greek has so much continuity with ancient that, if you know ancient, you can read plenty of signs and pick your way through pamphlets at museums and archaeological sites. Every Greek I have known has valued that continuity and history. The proposed change -- rendering any text printed prior to the revision obsolete and eventually unreadable -- amounts to cultural suicide.
Maybe you can recognize the continuity as a native Greek speaker. As someone who has learnt Ancient Greek that didn't help at all when I visited Greece. I mean even the letters (some) are now used differently.