HELP : All Installed Software Uninstalled Themselves

First check that you haven't been logged in with a temporary profile or that you didn't accidently reset Windows using the keep nothing option. Check the folders where you installed your programs, games and see if they are still there. It would be an extremely unusual, unique situation for all apps to just "uninstall themselves", such a thing would need user interaction at some point.
The missing restore points may suggest you have had a Windows build update, possibly from 1909 to 20h2 although even this doesn't usually remove all apps (some may not be transitioned if they are known to cause issues). See if you have a Windows old folder on your C drive.

pronetopanic said:

... all of my installed programs uninstalled themselves ...

Why do you think that?

Denis

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pronetopanic said:

... And when I go into Program Files which is where they should be, the folders or .exes don't exist either ...

Somebody or something has done that deliberately.
- If the folders & files in Program files are gone then even some unknown form of Registry corruption can be ruled out.
- Since the icon-less shortcuts still exist, it points towards Program files contents having been deleted rather than programs having being uninstalled in any normal manner.

Assuming that nobody has had physical access to your computer or direct control [through your home network] at a very high "system" level of privilege, malicious action by a remote user probably means malware has been planted & has taken the deletion action.

I suggest that a malware scan should be your first step even though I do not recall anybody having reported similar symptoms before.
If nothing is detected then do a Windows defender "offline" scan next. Windows Defender Offline Scan - TenForumsTutorials


Best of luck,
Denis

Apart from checking for malware as Try3 suggests, if you know for certain that no one else has had physical access to your machine it would be of help to detail exactly what the issue with "one specific app" as you originally stated was.
What was the app, what was the issue, how were you trying to resolve it?
A lot of software when uninstalled the correct way will pop up a dialogue during the process asking if you want to remove settings, custom files etc, depending on the type of app so I find it difficult to believe a mass uninstall could be automated and account for the variety of possible confirmation dialogues presented, at least doing it the correct way. Not impossible, just extremely unusual.
So that leaves user interaction, especially as you say the app icons (shortcuts) are still there, knowing what steps you were taking that led to the current situation may help to determine what happened and whether you can rectify the issue or not.

Pejole2165 said

First check that you haven't been logged in with a temporary profile

Information on temporary profile- and if you read this, you can see how to check:
Fix You've been signed in with a temporary profile in Windows 10

I have a Windows.old folder but the program files don't seem to be in there either.

In the midst of sorting an issue with one specific program.... My system restore points all disappeared before the issue too

There seems a contradiction here. Literally taking the description you give, you had a build upgrade. At that time your programs were intact. But you say Windows.old includes none of the programs you're concerned about.

Subsequent to that upgrade, you then say your programs disappeared whilst trying to deal with a problem related to one program.

It doesn't seem likely that both could be true- two events at different times related to programs disappearing.

Considering

My system restore points all disappeared before the issue too so I am unable to restore back.

Restore points are deleted on any upgrade and are only applicable to the current major build.

Perhaps your only hope is to try rolling back to the previous build in the hope you're wrong about Windows.old.

Unless -- you have followed the endlessly given recommendation here to routinely and regularly use disk imaging and you have a recent disk image - e.g. using Macrium Reflect (free)- of your Windows partitions.

This means you can almost always get back to a previous good state (and have a full backup of imaged partitions) without technical help - even if your disk fails.