Why is no one fixing or being honest about issues with custom gamerpics not uploading on...

Like the previous post said there is not an issue with uploading gamerpics the option was disabled during the pandemic going on at this point in time.

Not sure why it would have vanished, perhaps you accidentally changed it at some point, as for why you can't upload/change it again, others have already explained, so I won't repeat.

This is the only information that has been given regarding gamerpics:

As people look to gaming for social connection, Xbox is seeing record numbers across Xbox Game Pass, Xbox Live, and Mixer. To streamline moderation and ensure the best experience for the community, Xbox has made small adjustments. Some features like
uploading custom gamerpics, club pics, and club backgrounds are temporarily disabled (as noted on https://beta.support.xbox.com/contact-us)

There's nothing wrong with the pic you're trying to use. The system itself is just disabled for the time being.

Custom gamerpics has been disabled in order to streamline moderation while more people than usual are at home using services.

You can see it on the Xbox Support site under notifications:
https://beta.support.xbox.com/contact-us

They haven't made an official announcement for when things will return.

Nobody in the world was prepared for this kind of situation. Millions at home and heavy servers overload. Microsoft had to compromise for all of us to continue with all other activities. I advise patience and understanding. This will not last forever.
Wish you the very best.