Can you tell me any side that does correct "preservation"?

i can't
in my opinion TOSEC is overdoing it with meaningless information tags while not making backups properly
i'm not familiar with cartridge media, hence can not comment on No-Intro - how good it's done
but i think at least their naming convention provide a good means for such implementation
What is missing for actual preservation is the attached metadata with more information. This is currently implemented on the redump.org website in a limited way. Ideally this data should be included with the binary copies that were migrated and should be replicated.
Also everything else that were with the physical media should be preserved (Cover, Manual).
indeed, you're right
i see .dat and everything derived from it (also CD images) as independent set of information on it's own.
website is merely a mechanism to produce it, there shouldn't be further dependence.
So what should be done to make it "real preservation" for you? For myself, including metadata that has more information how the dump has been obtained would be a good starting point.
names should change.
they can hold a lot of this meta-data associated with source material.
as of now they basically serve only to identify title and then separate records - avoid collisions.
they could describe source medium better, down to edition at least - as far as it's possible.
for example, currently 'many-to-one' relationship from db is being reduced to 'one-to-one' in .dat
when several editions would yield similar CRCs, this information is lost outside of redump.org
this problem will escalate with time (and it's only one from several)
would somebody want to add covers or manuals now for PSX CDs - an independent project linked with redump.org images -
he'd be faced with fact that it's impossible to do so without manual examinination of records on redump.org website