SD cards are flash storage. If you don't understand how flash storage works then...
Also there is no such thing as "lock files" the card is either formatted as fat32 or NTFS, neither of which support locked files. Just because YOU can't delete them on your dash cam doesn't mean they are locked, it means your device is preventing YOU from deleting them.
Dash cameras are nothing but computers with a camera lens and sensor when it comes down to it, likely running some build of either Android or Unix.
Dash cam makers don't care if you are destroying your SD cards
There's no reason to spread misinformation that will increase wear/damage other peoples devices.
saying "you need\should format your SD card every month" is different then saying "your dash camera needs you to format your SD card every month because that makes the DASH CAMERA work better while increasing the wear on your SD card causing pre-mature failure"
As it is SD cards are NOT designed to function as camera storage and that is likely why these manufactures are having you do nonsensical things to your storage media. These devices would better be served using a similar sized SLC SSD.
A good example is the Comma AI devices. Anything over 32GB is using SSD storage, even a 250gb unit. You can easily get 512GB SSD cards with good read\write performance but i'm sure this manufacture knows they will crap out and be riddled with RMA claims for silly SD cards.
Here's a link to learn more about flash storage if you still are questioning anything I am saying.
Discover the origin of flash memory and its use cases. Examine the pros and cons of flash memory and the distinctions between its different types.
www.techtarget.com