You might have an alternative to gargantuan templates. It’s not as convenient but have you tried File>export>selected tracks? Then File>import>track archive? It’s not as convenient because you are not loading inserts into an existing selected track but instead opening a new track with inserts, send and corresponding FX track.
IIRC this will/should save the inserts with sends, routings, group, and fx tracks. Please let me know if it does not with a repro. It seems there were saving issues depending on the type of track, audio or instrument, but it’s been a while.
Track presets…only good for inserts on the selected track.