I did address them. You can't because balancing 2-4 sides or 8 Demigods is easier than balancing 100 skills. This makes your choice of side or class infinitely less likely to be a game-breaking error. Additionally, in Supreme Commander and D&D, there ARE some ways in which you can change, you can dual-class under certain conditions, capture or trade engineers.
Your examples are not changes, they're additions - you can't change your side in SupCom, you can only add another one, through play. Ditto for multiclassing.
You're just pissing on semantics and totally ignoring my point. I'm not arguing for infinite skill points to buy everything, I'm arguing that if you have a skill point, you should be able to put it in whatever the hell you like. In WoW, if you have satisfied the pre-req talents, you can place your talent wherever you want, regardless of what your other talents are. I've even put italics on the relevant point, just so that you don't miss it and pick some other entirely irrelevant fact of their system.
You are still wrong - you cannot place your talent wherever you want regardless of what your other talents are - you don't have enough points for every possibility. I italized the important part of your statement.
Even if you can't, then that's still a minimum, compared to every other class. If you're a Fighter, you can pick whatever new weapon specialities you like, regardless of what the old ones were. With mages, you can memorize any new spells within your slots, regardless of before. Etc. You've got one poor example, against how many I have. Try more.
So first you want an example, and when provided it's not enough? How many do you want? Here's another one: the Sacred RPG series has your character gaining the option to get new skills as you rise in levels - there are more skills than skill slots. How about the majority of Korean MMORPGs (played by millions)? Almost all of them use a branching class system - choosing one sub-class, locks you out of the abilities and everything else that goes with the other sub-class.