News reports of the end of MP3 are dead wrong. The media received False News and published it.
All that happened is the patent holder stopped issuing licenses because they are no longer in control, so there is nothing to license. To misdirect the media, they are trying to imply that their loss of control of MP3 somehow is "the end". Because instead they want a switch to newer methods that they control therefore must be paid for. The media that usually does not grasp anything beyond superficial is just repeating the self-serving story.
Of course new rips shouldn't use MP3. But as the most universally supported format (car radios use it!) any true end will be decades from now, if ever.
The user misunderstanding will spread, with people converting their existing MP3 files to FLAC or AAC or whatever, just making things worse (MP3 audio in a larger file size???). But if original uncompressed sources are available for MP3 files that have audible compromise, re-ripping to a better format might be useful.
I've been using FLAC in recent years, but have so much vinyl still stacked up to rip for the first time that I won't re-doing any early-years MP3s unless I find a bad one, which is actually quite rare. I've played LP tracks in parallel with MP3 rips of them I did 15 years ago and switching back and forth, they are virtually identical, certainly no cause for re-rip. (Where I find more difference is LP vs. commercial CD, with the LP sounding richer but the CD having more bass.)