Apps Extremely Slow to Start

Please let us know do you have Mechanical Drive or a SSD?

Please check in Safe Mode:

https://support.apple.com/en-us/HT201262

Note: Safe mode prevents your Mac from loading certain software as it starts up, including login items, system extensions not required by macOS, and fonts not installed by macOS. It also does a basic check of your startup disk, similar to using First Aid in Disk Utility. And it deletes some system caches, including font caches and the kernel cache, which are automatically created again as needed.

superherobyday wrote:

"Please let us know do you have Mechanical Drive or a SSD?"

I'm not sure. Do you know how to tell? When I pull up "storage" in the System Report, I can see the hard drive, but it doesn't specify SSD or HDD.

"Please check in Safe Mode:"

Gave it a whirl. Apps were just as slow in safe mode. Maybe even slower lol.

The section, Physical Volume: Medium Type > Rotational - Meaning you have a mechanical Drive (HDD)

Thanks for checking into Safe Mode.

You need a backup because, based on your symptoms, your drive could completely fail and stop responding at any moment.

You Will need a replacement for it, and you may not be able to salvage ANYTHING off it directly, especially since it is encrypted. Your backup will be essential for restoring any files or Photos you have created.

You need to make whatever backups you can.

You need to be shopping a replacement drive, at least as large as what you have now, and an SSD drive is strongly recommended. You may need to replace the drive cable as well.

An external enclosure to mount the new drive while you set it up can be very handy.

If it was perfectly fast in safe mode, slow in regular mode, "it's something you added".

Your original drive has lasted far longer than expected, and based on a preponderance of evidence from hundreds of complaints posted here every day, you need a new drive, and likely a new drive cable as well.

What is the date of your most recent backup?

Please post back if you do not already have such a backup.

that number look up to:

Seagate Momentus 5400.6 ST9500325ASG 500GB 5400 RPM 8MB Cache SATA 3.0Gb/s 2.5" Internal Notebook Hard Drive 

a rotating Magnetic drive.

You may need to focus on making a more recent one, without destroying the one you have. Unless a month ago is good enough for most purposes.

With SSD certainly there is advantage of speed over Mechanical Hard Drive.

With safe mode it does clears caches & doesn't load 3rd party extensions so good to check if that solves the issue.