MiddlePath, I disagree that “they..are the ones doing it right”.
For divrei Kodesh purposes (speaking in Israel for secular purposes is a different matter):
Just because Ashkenaz doesn’t have the precision to distinguish a saf from a samech does not mean that they should revert to Academic/Modern/Zionist Hebrew (adapted from sefardi havarah specifically disregarding their Mesorah of Ashkenaz havarah) and use a tav. A Saf is still far better.
Similarly, the non-guttural ches is arguably better than a simple imitation of the letter “hay”, since Ashkenaz does not have a mesorah for the guttural ches.
On the flip side, the non-askenazic havarah does not distinguish between a patach and a kamatz. That can’t be authentic, either…(Nor do both Ashkenaz and Sefard differentiate between a tes and a tav. So if the similarity is an issue…)
Ironically, the Israeli children are taught and/or speak a real cholent of a havarah with mixed ois and ohs (worse than their American counterparts who are generally consistent one way or the other), and even take it a step further with things like dropping the “hey” altogether and pronouncing it like an aleph.
Uncorrupted Ashkenaz (ohs) and Teiman are the closest things to the genuine deal, with Teiman being closer.