This was patched to just work off regular ifs in something like .17 or so.
If there has been a regression or not, one cant be sure without testing.
BUT
As of .22 when I first read that flame war topic on the subject - topic which I bet epic has since decided to delete because information for us users is a dangerous thing. As everyone knows we could start asking nasty questions about epic’s stupidity… - the issue had been stably resolved.
Older shaders that used custom were left as is in the classic epic way.
(It works, dont touch it).
This fact doesn’t mean that you shouldnt still just use the custom node.
Doing so is future proof.
Using the regular if you take a gamble on when Epic f*s stuff up next.
And if today it works, there’s always tomorrow 
Even if from reading it seems that even today it just doesn’t work right anymore…
Disabling features by distance is not a novel concept. Burks was doing so in some example water materials way back in 2020 or even before.
Generally it works well on instanced objects and such, but not on large objects like landscapes where both branches have to be calculated anyway.
A work-around for that was to limit the UVs where the branch occurs.
Basically.
Up to 10m you have UV0 custom with whatever up close and personal texturing/effects.
10m to 40m you have uv1 custom with less but not notning.
40m on you have uv3 custom with a whole lot less or next to just a texture.
Now, as of .22 you could do this with just IF statements.
If you have go go into to a custom node now i cant be sure.
Hoerver the trick was using the UVs rather than making calcs on the spot.