It can be done, but it can't be easily done, and that's the main problem here... you may try to maximize any hardware, but it needs time, specific tools and skills... just like in the previous gen with PS2: at the start of the gen, many devs had hard times, then it went better and better after two or three years of dedication to the hardware...
But they won't do the same efforts for Wii this gen, as most of the "core" gamers are already playin on PS360, and if these gamers have to choose between a beautiful version with perfect online and a "standard looking" version with average online, their money will go to the first, obviously...
I'm sure that if Wii was more powerful, even if not HD, many devs would take the time to do good ports: they don't hate Wii in itself, they don't like its limitations, that's all...
And the diiference in budget may be a good point for Wii exclusives, but in this case, a "difficult" Wii port will take a lot of time (and money) because of the downgrading of graphics which still need to look great, and the specific controls to be added... plus, revenues may be way lower than on PS360 anyway, due to the very different userbases: so it's a vicious circle...
"A beautiful drawing in 480i will stay beautiful forever...
and an ugly drawing in 1080p will stay ugly forever..."
