Yes, there's a HUGE range of quality in on-line degrees these days. Many of the degrees are sold by degree mills calling themselves universities and cheating the hell out of their students. Almost all MOOCs are watered down subset of an on-campus course.

But the on-line degrees from these top tier schools do not suffer from that.

I am curious as to your basis for this statement. Have you done many? Why would a prestigious institution be willing to dilute its brand in that way?

You will at least have a rich gitHub repository if you go through it. If you try your best you will also learn a lot and make connections.

The advantage of a part time masters is that the connections are of a much higher value. During your undergrad you and all your connections will go on the job hunt. In a part time masters some of your connections will be hiring.