I think you know my philosophy on this issue.
But, let me elaborate a bit more!
I think it is sad when schools mislead new students by calling their art something different than it actually is. There should be no shame with creating a Martial Art. Others in the past have done it... people in the future will also. The Martial Arts are the opinions of combat principles. Most human beings understand combat. So, it is not uncommon for someone to create their own M.A..
My only solid issue is... they should utilize 'standards' and 'philosophies' from succesful systems as a root for morality in their new Martial Art. They should also not try to delude themselves or others with un-tried principles.