Signet is a nice solution but it's centrally controlled and won't meet the needs testnets provides for its traders, I'd classify it under regtest in terms of providing a testing environment. Developing your own signet will take you away from the main signet, hence you may never interact with other projects on the main signet. So the self developed signet you shared may not be transferred to other signet.
Murch on stack exchange has two responses consecutively for the both links you shared.
1.
https://bitcointalk.org/index.php?topic=5501712.0While this may be a good solution for some use cases, it should perhaps be pointed out that getting coins on one signet will not transfer to another signet, i.e. acquiring coins on this new signet will e.g. not able you to interact with users on the main signet.
Link12.
https://en.bitcoin.it/wiki/Signet#Custom_SignetStarting your own Signet helps with having a test environment, but doesn’t put you on the Signet other projects may be testing on.
Link2