The upcoming 5.0 release brings with it the terrible Gutenberg editor that Automattic feels they need to try to cram down the throats of WordPress users everywhere.
This editor basically takes normal tasks that were / have been easy to perform and adds unnecessary extra steps in an attempt to make WordPress' editor look more like that of Squarespace.
To perform a simple task such as using bold, what was once a single click process has been turned into a two to three click one, reducing productivity of users by a large margin for what should be a simple task.
For the process to get to bold, it shows up like this with a bunch of expandable categories and a search. Want to bold your text? Well to make that intuitive, we've made it harder for you to find the bold button! Now you get to search for it in a menu instead of just clicking on it.
Can you keep the classic editor?
Yes, you can. Thankfully the WP team is smart enough to include it as an installable plugin so that you don't have to be forced to use Gutenberg and for those who are currently on WordPress, I'd recommend installing and activating it now to prevent Gutenberg from taking over when WordPress 5.0 comes along.
For those who want to try this beast out, you can actually install the Gutenberg editor on your blog now (as a plugin) but I'm not sure why you'd want to do that. The best bet, test it in a dev environment first and make your decision. Fortunately, you can still use the classic editor even when this 5.0 release hits so you won't be stranded in a desert full of frustration.