It is a complex question. I have several reasons:

1. Traditional education has a long history. People trust it. It has results. And, people resist change in general. So they will look at something new with a skeptical eye. And, when you’re a manager of a company and you have to decide who to hire, do you hire a graduate of a well-known university or someone who earned an online degree? If the candidate turns out to be unsuitable, are you more likely to be blamed if you choose the college guy or the other? The answer is clear and this is why people don’t value online education as much as a degree (yet).
2. There is no one to decide which website provides the best education (or maybe there is, but I don’t know?). Also, standard tests, such as when taking an exam, are generally not available with online training. So how good are online tests at actually confirming that the student has learned the courses? Another reason to devalue online education.
3. Money. Education is expensive, and for valid reasons. Online education is much cheaper, due to the economy of scale. Also because you are creating a product once, then it is almost free to distribute it. So universities have an incentive to downgrade online courses. It is your business that would suffer otherwise. To be fair, some universities have embraced online education as they can digitize their courses and sell them online for a nice profit. To stay ahead of the competition, they have to bet on quality versus price. So this reason could disappear over time.

I think the situation will change over time. But it will take time. Online education gives everyone unique access to higher education. And it is especially useful when you have to constantly update your knowledge and skills. So it’s perfect for professionals.

As people begin to trust online education more, standard online college education will become more trustworthy. Especially when more and bigger universities put their resume online, including the standard exam.

Now, virtual reality brings a unique experience to education. One that can be used not only for online courses, but also for standard brick and mortar universities. So I think it’s going to revolutionize education. When you can be emotionally involved in historical events. Or when you can redo historical experiments, emotional involvement helps you retain more information.

Therefore, the advantage of standard + VR education over standard education will be so obvious that you will be at a disadvantage when you do not offer virtual reality courses as part of your curriculum. Another reason that will accelerate the adoption of virtual reality in education.

Of course, this is just my point of view.