always hangs on startup

Do you need all those external drives connected at the same time?

A common reason for a beach ball is a drive that is too slow or not responding.

I'd try disconnecting unnecessary drives and see if that makes a difference.

You Chrome and its evil keystone daemons.

You should completely remove them. See https://chromeisbad.com

for an explanation of what they do and how to completely get rid of them.

After that, delete FCP and download a new copy from the App Store.

You also have a lot of old kernel extensions. Many may not work, and could cause trouble.

This indicates that a system has been upgraded year over year for some time.

It may be a good idea to start fresh, and it is not nearly as hard as it used to be.

Make an up to date backup (preferably two, as we are about to delete your data...)

In System Settings->General->Transfer or Reset, click Erase All Content and Settings

Then after your system restarts as if for the first time, migrate the content from your Time Machine backup,

but ONLY the user accounts (no applications, no settings or other files).

It will take a bit to reinstall software, but you will have a clean and performant system.

Where exactly do you see the spinning beach ball. Post a screenshot of when this happens, with any error message.

Please post an EtreCheck report https://etrecheck.com giving the application Full Disk Access in Privacy & Security System Settings. Copy the report and use the Add Text button to paste the result into reply box. 

I've never seen that before I don't think: the application opening without opening a library.

philipdadgad wrote:

Solved. The EtreCheckPro told me which startup items to delete. Thank you for your help.

Can you expand on that? What did you delete? It may be useful for others.