I think largely we deal with it by still trying to make it all fit, or as much of it fit, as we can. For instance most of everything revolving around Mandalore is still canon on some level or another. The Pacifists & TCW version of Death Watch have been added to the mix but everything else still remains as well so far as the EU is concerned. When the new guide books like the Guide to Warfare come out, they still contain as much as possible, though some of it of course gets tweeked(and the odd bit changed or erased). Do I like it? No I don't, but there really isn't another option available. Add to that of course that I've been following Star Wars for a long time and have seen a lot of stuff come and go. Now if it was official, not just theory based on OOU comments from Filoni, that Jango Fett was never a Mandalorian that would be a big mountain to climb since it would invalidate a lot(from RC to LOTF) - but as it currently stands Jango is still Mandalorian so it doesn't matter.Open Seasons, RC, and even the Mandalorian Marvel stuff is mostly(almost all) still canon. The biggest issue coming out of The New Mandalorian episodes were geographical ones. How could Keldabe be the biggest city on Mandalore when Sundari is there? If Mandalore was a nuclear wasteland where were the massive forests and varied terrain that housed the true Mandalorians and their culture? Since then it has been determined that Keldabe is still on Mandalore, and that the whole planet is not a nuclear wasteland. It still makes it difficult to reconcile character POV's from the RC/IC series - but none the less it is still all there. Other TCW continuity issues are harder to fix. Even Piell, well that pretty much is unworkable short of some deletions - Adi Gallia, much the same. Darth Maul not being dead? Well, thats just nonsense - but its nonsense one has to put up with if they want to move forward with the story. I used to have a more personal canon myself but have moved away from that over the past decade or so to try and include as much as possible, something which is also still the LFL view(at least for now).