Looks like many widely used wallets do not support hardened child key derivation. E.g. Sparrow, Electrum, etc.
If so, why has it made into the standard, what would be good case examples?
Speaking about the practical side, are there any wallets that can operate derivation paths with hardened child derivation at the receive/change level? (i.e. the last component of the derivation path).
If so, why has it made into the standard, what would be good case examples?
It has become the standard because unhardened derivation is the direction bitcoin core has decided to go, and they have a lot of influence as most wallets want to be compatible with the latest and most popular bitcoin client.
These backward incompatible wallet changes proposed in 2020 was considered to be "somewhat aggressive" as expressed by the previous core maintainer Pwuille in a github post (https://github.com/bitcoin/bitcoin/issues/20160#issuecomment-1244613676). Pwuille also indicated users should be allowed to user either hardened or unhardened in case they were concerned with the risks with unhardened paths.
Up until a few years ago hardened derivation paths was the standard on all wallets as it was the most secure.
Unhardened paths is a more recent change which is factually less secure than hardened paths.
With unhardened derivation, if you have a child private key and the parent xpub, the parent xprv can be derived.
Bitcoin Core now uses the various derivation path standards all of which use unhardened derivation. So allowing individual child keys to be exported exposes the user to potential wallet compromise.
These more modern wallets are a preference choice by wallet developers and those pursuing the new "descriptor wallets" approach.
If you want to use hardened paths you need to use older software (not a great idea), build a solution yourself using a library (better idea but be careful "rolling your own") or leveraging a tool that allows you to navigate custom HD key chains/paths.
https://bitcointalk.org/index.php?topic=5395792.msg59975673#msg59975673
