The other day it hit me that it seems perfectly legal (and even relatively common) to sling target lock tokens onto ships that don't have the target lock action in their bar.

I clued in when I was looking at a Phantom build with a Fire-Control System, and realized that Phantoms can't target lock, but I've frequently seen them running around with TL tokens due to the FCS.

Previously, I'd had TLs conceptualized in a "fluffy" way that has nothing to do with the actual game mechanics; ie. a ship without the TL icon doesn't have the ship computer technology to maintain target locks, and therefore can never have TL tokens.

Now it seems obvious that I was wrong, and there's multiple ways for a ship to get a TL without having TL as an action option. Is that correct? Like, there's nothing stopping Colonel Jendon from giving a TL to a basic Academy TIE, right?

Yes, it is possible to acquire a target lock without having the ability via FCS or having them handed out by characters like Dutch (although all rebel ships to date have the TL ability).

I visualized this as ships without the TL action but have the FCS need "longer" to acquire a TL. For example, an X-Wing has the TL action. You fly into range and BAM! He's locked onto you, even though he's facing the other way. The Phantom on the other hand doesn't have a TL action but has a FCS so he can still get a TL but he has to 1) get the other ship in arc and in range and 2) designate the target by firing the guns at it --- hence you can't use your TL on the first attack.

As for others that can pass TL tokens, just imagine it as some special gizmo that can receive target locks but cannot make it their own. For instance, some modern fighters can scan the sky (with radar) and pass enemy position and information to other fighters who have their radar systems turned off.

Remember that these are upgrades, so while the default Phantom may not have the ability to get a TL, the player may "upgrade" his ships so that his pilots are flying with FCS-equipped Phantoms, which cost more.