Nicely said. I did do that for 1.5 out of the 4. While I didn't state it well, my argument was meant to be for replacing one or two of them, not all of them.

Voice is probably the hardest one to replace all 4 of them on.

For Facebook's network effects, I mentioned Twitter which is not one of the four. I did mention that my main use I've replaced with Google Photos. I did that because it's free & great. If I hated Google, I could use several paid services that offer similar benefits. Snapchat is becoming more popular with the older people I know. Instagram was great before getting bought out by Facebook so we can't count them now.

I think maybe one point that needs to be made, is if you want a "free service" you must be willing to let your data be sold. That is the big problem that many people have with a lot of the above free services.