Cockpit voice recorders are frequently overwritten because they are limited to only 2 hours in the US. Pilots' unions have pushed back on increasing this, stating they have privacy concerns.
Flight recorders are fireproof / water proof / shock proof devices on the airplane and are limited in size of memory they can have. On the factory floor, on the other hand, one can store lots of data or/and upload it to some massive cloud storage for backup / retention. It is totally different ball game.
It's not at all a technical limitation here. The cockpit voice recorder will record 25 hours in the EU and only 2 hours in the US, and that's been the case for years.