This is not a good trend

Perhaps these issues could be solved more easily by distributions taking all bug reports first. E.g, users are always directed to the distributions bug tracker for any software running on the distribution - flatpak or not. Though I thought fedora had this with their crash reporter?

It could be made very clear that they need to do this and the software may have modifications[1]. This would solve the issue of upstream dealing with reports that may not necessarily apply. Thus, not wasting their time/effort.

Perhaps even the software developers themselves could do this, force all distribution users to report to the distribution first while automatically closing new reports that have not done this.

Finally, FOSS applications which have trademark issues (legal threats) can be dropped from distributions to avoid legal issues, ensuring that users only obtain the software from official and authorized sources.

[1] Though, I figured this was common knowledge, a good chunk of software across all distributions has always been modified in some way to make it blend in with the distributions other software, this is standard practice. For example, regardless of distribution you'll rarely get a vanilla kernel (no modifications) or vanilla glibc, vanilla plasma, etc.