No. The primary person behind F, Walt Brainerd (author, standards committee member, and creator of Fortran.com) passed away. Some people, including me, did use F and ELF90 to transition from FORTRAN to (what was then) modern Fortran. There were some discussions in comp.lang.fortran of why the Fortran subsets did not catch on. The problem is that while everyone would agree that Fortran 95 or Fortran 2018 is bigger than it would be if it were designed today, you cannot get a consensus of what should be allowed. For example, although I liked the idea of F, I think you had to use the DIMENSION statement and provide all specifier names, so that what I prefer,
real :: x(n1), y(n1,n2)
write (*,*) x
must be written in F as
real, dimension(n1) :: x
real, dimension(n1,n2) :: y
write (unit=*,fmt=*) x
There has been discussion here of creating a subset through FPM defaults.