There are a few advantages to a track saw vs a jig.
First being the guided plunge action, which allows you to start and/or finish your cut smoothly on the inside of your workpiece. Extremely advantageous for any hardwood flooring repairs, sink cutouts in wood/other countertops, etc.
Second would be ease of layout, setup and clamping. If you have a square or protractor attachment you can square up without having to mark front and back of the workpiece or without a framing square. The clamps allow you to clamp from beneath which keeps them out of the way. You could probably route a t-slot on the bottom if you wanted, and put on some grip strips just like a saw track as well though.
But overall if you already have a tablesaw and a circ saw then a jig like this is probably fine for most occasional carpentry.
To the OP, I wouldn't buy a tracksaw just for shop cabinets. Kitchen cabinets probably. I'd just clamp a straightedge.
TBH, I don't think a picture perfect edge is all that vital for shop cabinets. You are probably using fasteners, dados, biscuits etc. If you need to perfect your plywood cut with a hand plane to get a better glue joint that's probably your best route.
However, if you see yourself going down a long road of lean'n'mean carpentry/woodworking with a small footprint, a tracksaw can cover many bases. I would still get a bandsaw for skinny ripping and a small router table if you don't have one already. This is my setup and along with hand tools, I can do anything. I also have a lunchbox planer.