Testing screen reader announcement of ellipsis vs. three dots

This sentence has an ellipsis…

This sentence has three dots...

<img src="…">

<img src="...">

Results

Chrome/JAWS at default verbosity doesn't announce ellipsis, but announces three dots as dot dot dot
Chrome/JAWS with "Punctuation: All" announces ellipsis as ellipsis, and three dots as dot dot dot
Firefox/JAWS is the same as Chrome/JAWS
Firefox/NVDA at default verbosity doesn't announce either of them
Firefox/NVDA with "Punctuation/symbol level: All" announces both of them as "dot dot dot"
Chrome/NVDA is the same as Firefox/NVDA
Safari/VO at default verbosity doesn't announce either of them
Safari/VO with "Punctuation: All" announces ellipsis as ellipsis, and three dots as period period period
iOS/VO at default verbosity doesn't announce ellipsis, but announces three dots as ellipsis
iOS/VO with "Punctuation: All" announces ellipsis as ellipsis, and three dots as comma ellipsis comma
Chrome/Talkback at default verbosity doesn't announce ellipsis, but announces three dots as three full stop
Chrome/Talkback with "Punctuation: On" announces ellipsis as ellipsis, and three dots as three full stop

Working conclusion

Three dots is more accessible than ellipsis.

I would argue that it's also more commonly understood, whereas ellipsis is an obscure typographical term that far fewer people will recognise the meaning of. However this is a subjective opinion, I have no data to back it up.

Presentational note

Ellipsis is larger than three dots in serif and sans-serif fonts, and smaller in monospace fonts:

… (serif ellipsis)
... (serif three dots)
… (sans-serif ellipsis)
... (sans-serif three dots)
… (monospace ellipsis)
... (monospace three dots)