Make sure the trees in pots are on full dwarf rootstock. This makes them last a lot longer in pots, and can lessen the need to root prune (bonsai methods). Most of no all fruiting trees can grow in large pots if on dwarfing rootstock

As for sun, most fruit trees do indeed need all day sun during growth. The thing is, most plants dont like full, hot sun, for the hwole 12 - 18 hour summer day. You can get away with dappled light for a bit, as well as some shade in the morning or afternoon, but they should get the EQUIVALENT of 6 - 8 hours of sun a day. That could be direct in the afternoon, or lightly dappled light all day.

Most trees dont mind shade in the winter. If anything its better for the trunks.

Putting the trees in pots will have a dwarfing effect on them no matter if it is on a dwarfing rootstock or not.

The sun that really matters for a fruit tree is from 10:00-2:00. If the tree gets that full sun exposure during that time period it will do just fine with some shade earlier or later.

Yes, a dwarfing affect on the tree above ground, which, the tree ill constantly fight to gain proper size, and the roots will still try to expand wider then the drip line.

Dwarfing rootstocks make the job easier. Its easier to grow a tree that maxes out at 6 - 8 feet in a pot, then a tree that wants to grow to 12 - 15+ (semi dwarf).

Its the same as houseplants. Some even "like to be pot bound" like some ficus, but even then, if lef in a pot too small, it will suffer eventually. Ficus tend to break pots from my experience leaving them.

I never said you CANT grow anything other then dwarf trees in pots, its just making LESS WORK for yourself, and trying to make the trees last as long as possible without stress.

Smaller tree = smaller root system = easier to grow in pots