I'm not aware of this being a known issue.

For whatever reason, there was always a difference between "Install MSI" and "Network MSI". 

One of them pre-populated and one did not.....Off the top of my head I can't recall which one was which.  My guess is that is what you are noticing.

There are advantages to both ways....when we do it's easier as you note.  However, some MSIs have so many options that specifying all the defaults cause the command string to be too long and fail.

I'd suggest testing both and if 1 works and 1 does not....it's one of those anomalies that was always there....

(Note: If I had to "guess" the "Network MSI" likely read the defaults and the "Install MSI" did not.....because for the "Install MSI" because it's tricky getting the MSI values, since it will need to be done during the "upload" or the MSI will not be easily accessible to read to get the details.

Craig,
I virtually never use "Network MSI" (which, BTW, is a complete misnomer, as the MSI to install doesn't have to be on a network at all, but can also be local on the device you want to install it on)).

It's "Install MSI" that always has displayed the Parameters, and now suddenly no longer does.

I just did a test, and in 23.4, neither brought in the MSI properties.....So I can't say which one of the two did it in the past....but I won't dispute your memory on which one you are sure did.

I can't find any defects to intentionally change the behavior, though I could see someone in dev deciding to "normallize" the behavior so they were both the same.  I can also see it just breaking unintentionally if they recoded a section and overlooked that function. 

I don't currently have anything older than 23.4 in my lab for testing to figure out when it may have changed.

I have plenty of existing Bundles that show the Parameters for MSI installs, so I know my memory is fine. ;) It's very possible that it was broken in 23.4 already, for the most part I skipped this version, at least I didn't create many new bundles using it. I'm almost certain it was still working properly in 2020U2.

Good Thought...I went back and checked some old bundles....I can see one Install MSI bundle that does indeed have the MSI values pre-populated in the ZCC.  Based on the Bundle Change Time Stamps as well as System Update History, I can see it worked in 20.3 and appears broke in 23.4 (Or possibly 23.3 which was not installed in this incarnation of my lab.)