The way that technology has changed how we live is very deep. We are not even aware of it most of the time considering that we are now taking all that for granted and don't even think about how we lived before internet got as wide spread as it is today and before smartphones became as advanced. However that has also led to the advancement of technologies and method used in remote learning and e-learning. As a result we live at an age where it's entirely possible to learn English online.
Having said that these techniques of online learning are not for everyone. The determining factor is not the quality of the program as there are some extremely well developed online English programs on the market, but the personality type and learning habits of the student. On one had the fact that we can now learn English online with the help of an online course is extremely convenient but it also means that the student needs to be both motivated as well as disciplined enough to turn on his or her computer and take that class. Students who opt in for the online learning methods are usually those ones looking for the most effective way to learn a language without having to spend their free time going to a class. But that also ends up being a downside of the online method as there isn't a group to motive them to "attend" the next class and keep pushing forward.
This new method of e-learning that allows just about anyone to learn English online is really just a method. It's not any better or worse than attending the class in person, it's just more convenient for some people. I'd strongly suggest trying it first before having an opinion about it as you just might discover that this type of learning is the best one for you.