Emulator

*SHA256

Thank you :-)
With this said, ≥ SHA256 should definitely be the default choice for Dolphin and warnings should be in-place for users stating the implications of MD5.

JosJuice wrote:

We won't remove the option to calculate MD5, since it (along with SHA1) is commonly used in lists of hashes that you can find online. Adding the ability to also calculate SHA256 makes sense, though.

Those hashes are used for integrity, not security, so they do not really matter that much.
As already mentioned, the goal is to provide some sort of comparison value (to verify whether a dump is good or not) against well-known public lists (such as GameTDB amongst others).

Is there even a database of GC/Wii game non-md5 checksums to compare to..?

Redump uses CRC32/MD5/SHA1, and GameTDB does the same. I don't think there is any database that is using SHA256, really...

I'm only seeing md5 on GameTDB. At least for the few (very popular) games that I looked at. MD5 definitely seems to be the most popular and it does the job (of testing integrity) just fine.

The only possible security issue I can see is if someone were to make malware for Dolphin and then manages to make its hash collide with a legitimate game for extra points.

I doubt anyone would go through that much trouble, because no one would check the MD5 anyway before running the ISO.

Not all games have all types of hashes on GameTDB, but those are the three types of hashes that the GameTDB database supports. https://www.gametdb.com/Wii/RSBE01 is an example of a game that has all three types.