why does final cut pro take so long to load

First, try deleting FCP preferences: To delete preferences, hold down command and option while starting FCP X and click Delete Preferences. The application will start in a default state, and open an “Untitled” library.

Reopen the library you were working on, set the preferences the way you like them, and try again.

If the problem persists, most likely there are third party software conflicts. If you have Chrome then it is known to complete cripple video applications because its “keystone” daemons and agents hog the system videotoolbox like there’s no tomorrow.

Third party “antivirus” and “cleaners” also very adversely affect FCP.

In order for us to know more please run the diagnostic tool Etrecheck and post its full report here using the additional text button below your message.

You seem to have several drives attached, including a 4TB drive that is basically full (some 200GB free, that is much less than 10%, and will cause slowdowns).

If you start FCP with only the internal drive connected, does it take this long?

Also: you seem to have many audio units, and there is a chance that some of them may be problematic.

If the drives are not the issue, then may a divide and conquer procedure is in order: deactivate the audio units, check that FCP starts normally, then gradually add them back and test.

Look under

~/Library/Audio/Plug-Ins

and

/Library/Audio/Plug-Ins

Early depends on where you are. I am in Portugal 😎