I wouldn't be surprised if that "much" was "most." I did a couple of small projects for a commercial fishing vessel a few years back to ingest NMEA0183 sentences and convert them to an AIS message (I think he was connecting it to a newer chart plotter that only had AIS input).
I recall asking if this functionality wasn't available off the shelf and the answer was that it existed, but it was difficult without also buying a lot of new equipment he didn't need. It apparently cost a lot less to have me do the data conversions (and I didn't charge much for it) on a small SBC than it would to have to buy new equipment and deal with installation, fitment issues, etc.
I recall asking if this functionality wasn't available off the shelf and the answer was that it existed, but it was difficult without also buying a lot of new equipment he didn't need. It apparently cost a lot less to have me do the data conversions (and I didn't charge much for it) on a small SBC than it would to have to buy new equipment and deal with installation, fitment issues, etc.