I turned this on in my services website and have tried to use it. My advice to all of my clients is stick to the old editor. While I can figure out how to use it, I am doing this all day, and I know something about writing code, and this is reminiscent of a code editor in some respects from the 1990’s driven by lots of keyboard shortcuts which I know none of you will remember because you are not editing every day. I just spent 10 minutes figuring out how to add a link in, when I tried to follow the guidance a search request popped up from Google (I am using Chrome), so there was a conflict in keyboard shortcuts, tried another way, and while I could get the old editor to work, added the link, the text was not changed! I had to hand edit it.
I have seen a huge amount of push back from WordPress veterans. I have tried to keep an open mind, but in this day and age, if it is not intuitive, people will not use it. This is not intuitive, you are going to need to keep a handy guide, which is really not acceptable for people whose day jobs are not developing websites. Maybe it is a way for WordPress to pull it back in to a smaller community of “experts”, I don’t know. It seems like a huge step backwards.
Avoid being caught out by the switch
I don’t know when it is scheduled to change, but you can take some precautionary steps right now. On your dashboard (the screen you see when you login) there will be an item on there introducing Gutenberg. There is also a button where you can permanently install the old editor (the one you are familiar with). Click on that and follow the instructions to install it.
As and when WordPress upgrades and Gutenberg becomes the default editor, you will have retained your old editor, so you can keep editing your websites without worrying about a new system.