[jcampbell1]

Just compare frozen boiled water and aerated tap water. Both will be cloudy when made in a tray and both will be clear when made in an insulated cup. It does make a minor difference, but it is unimportant.

Also notice the radial pattern that the internal fractures take. This is inconsistent with bubbles and perfectly consistent with internal stress due to expansion pressure.

[foobarbecue]

I think the effect of boiling is negligible because air dissolves back into the water as the water cools. I don't understand your radial pattern argument. When I look closely at the lineations in the ice I see that the streaks are composed of individual spheroid voids. Not sure how fracture could do that.

[jcampbell1]

You can pour water straight from the kettle into the trays and cover it.

https://www.dreamstime.com/stock-photo-ice-cubes-image179488...

In that photo I see a few gas bubbles, but it is dominated by radial expansion fractures and cloudy high pressure ice in the center. That ice will crack when put in water. Clear ice does not crack.