This is far from the first BattleTech product that compiles material from prior books.
No it is not but given that the book it replaced (TRO:3039) took the time to rewrite a good cunk of the stuff carried over from earlier books. TRO:SW very disapointing in that it was a through and through copy/paste and generally far inferior to the book it replaced.
And in addition to the text not being even remotely updated, by the time TRO:SW was released, as the OP points out the carried over artwork was just over 30 years old and looks atrocious by the standards set by our own TROs from a couple of years earlier (TRO3150).
TRO:SW was not aimed at new players, it was aimed at making money from existing assets.