I’m not a met. But to answer your question nothing was ever accurate at d7. In fact, the original gfs had the short range AVN that went out to 72 hours and the longer range MRF to d10 which was (and still is) ultra lala land. Cmc went to d6 mainly available on the shitty graphics environment Canada. The euro was run once daily (12z) with plots in 24 hour increments. And it wasn’t available until around 7pm. Some of the mets had better access but we would wait for unisys output to d6. Later d7. Few had access to eps so one of the mets would describe it but were not allowed to post it.
Accuracy through d4/5 is better vs 15+ years ago but there’s so much availability and so much trust that everyone presumes the models sucked. I remember pd2. The euro had the idea but the track was way off until d4 when it locked in. Same for all the biggies.