I have a child in the industry who has worked on a few projects and is currently working in a big, name studio.
Having a degree is in my opinion very important for several reasons. First, you never know when a degree will be valuable in the future. Secondly, a degree will give you a strong foundation if it is art/animation and a structured curriculum.
Third, if you do well, many of the instructors at top art and design schools have industry connections ,which can help you considerably. Also a college program will also expose you to all areas of the animation pipeline,which is very crucial as I will note below.Finally, a college/art program will expose you to critiques ,which can be very valuable in improving your work. It is hard to improve solely watching videos without feedback.These critiques come from both the instructor and from other students. Watching what other students are doing is also very educational. Working at home on videos won't give you this and many of the other benefits that I described.
Now if you insist on not getting a degree,which I think is a mistake as noted above, there are a number of things you need to know and do.
First, in the 3d computer art field, there are a number of sub-specialties that you might be interested in. You have concept art( which is very art oriented), you have modeling, which also is art oriented, you story boarding,which is very art oriented, and character animation which is very art oriented. You also have a number of other disciplines that are part of the animation pipeline that are a bit less art oriented but more computer oriented to various degrees such as lighting,rigging,particles and dynamics /special effects, environmental specialists, skinning, post production, programing tools etc. I would suggest that you take videos or courses in each of these subjects to see what area of interest you have. Gnomon has a lot of good videos as does Digital Tutors and other such organizations. Also, taking some foundation courses in color, design, drawing etc. , can also make your overall art work and advanced courses much easier than if you don't have a strong foundation in my opinion.
The problem with the videos though is that you don't get feedback unless you take them as a course that includes instructor feedback. Even with this, you won't get to see the work done' by the other students.
Bottom line: Yes, you can develop the skills necessary by watching videos and practicing what you learn from professional videos. However, in my opinion, it will be MUCH MUCH harder to do that than attending a school with a tough, structured curriculum. You will need amazing discipline and drive, not to mention a LOT of innate talent. If you don’t want to go through all this, you can get a grad degree in computer graphics/animation and do programming for the studios. They do need good programmers and people to develop tools out of the off the shelf software such as MAYA, Houdini, Zbrush etc.
Hope this helps.
PS majoring in computer science can still get you into a grad program in 3d computer art/animation. I know that SVA and SCAD takes people who didn’t necessarily graduate in an art or design program. HOWEVER, you will need a decent portfolio to show that you have potential.Schools like University of Pennsylvania have grad programs for people with computer science programs to facilitate and expand their computer knowledge into graphic and motion arts. However, this leads solely to a programming type of job if that is what you want.