For comparison. Your 508 is sold in may countries in EU and primarily FR. The Gen 2 is only sold in certain countries like GB, SA, AUS but MY being the most sold in. While it may seem the car sold a lot and OEM parts are a lot for it, it is gradually running out. There are no reason to make spare parts for these cars where the amount you could probably count with your fingers. So you will run out of parts. Wira suffers less due to the similarities of many past Mitsubishi models.

If you compare Preve/ Suprima to Inspira, no way Preve Suprima will outlast Inspira that is based on Mitsubishi Lancer platform that was sold worldwide on parts.