In general, yes all the above are to blame, but who's decision is it for the Okehampton service? Are GWR▸ being forced to run it, or is it there own decision?
They are being paid to run it. Also
DfT» have made statements asking GWR to look into providing more services.
However the point I was making is that a shortage of drivers and stock generally is not just down to GWR but for reasons explained elsewhere the actions or non actions of
NR» and DfT have also contributed. The extent to which this affects Exeter crew I do not know.