In some instances they do increase other visual settings other than just resolution.

Breath of the Wild there was differences in the Anisotropic filtering.
https://www.youtube.com/watch?v=gpqaTdflkNU

Super Mario Odyssey has reduced lighting quality. No bloom in distance light sources.  Shadows get a quality reduction. Distant objects have reduced polygon complexity.
https://www.youtube.com/watch?v=yt73EVyOBoQ

So it does happen. Resolution is just easy...

They've discarded the fan and have a cheaper battery in place. I think this is why you wokt get a TV mode, the system cant safely deliver Docked performance.

The Switch Lite can only display in 720p due to the new CPU and power saving software, so yeah even if you could :/

I have no doubt the Switch lite can on a hardware level support output to a TV. I believe the reason it can't be docked is down to the cooling in the Switch lite being unable to safely run the device with docked performance. If that isn't the case then it's just laziness on Nintendo's part. 

This is kinda like asking like "can I mod my 2DS to output in 3D" though.

2DS doesn't have a 3d screen. a Switch lite has a usb-c port.

You could mod a 3D screen into it. Still kinda pointless when there's already a model that does 3D/TV mode.

The battery is what made me mad. Just like with iPhone making phones thinner.

I can do with a little more weight if battery have more working time.

are you sure it relies on just passive cooling? .....

Sorry I went off to check online, no from the trademark on the Switch lite I found this.

so yeah, it does have a small fan in there capable of spinning up to cool that tiny bar of copper, I was just thinking there are some tasks that even a more efficient chip would require some cooling to pump out, the Switches fan is rarely on in any major way (audible) in handheld mode but if you put your hand over that vent, it's always pushing some air through the system, you can't get ps3/60 quality graphics in a handheld just yet with just passive cooling. (in b4 someone links a $1k costing phone running a cod clone, what I mean is at a price where you can sell it for $200)

Keep in mind as well that the dock was designed around the width of the original Switch.... and people still managed to bash their screens off the thing and scratch them up, now imagine dropping a far skinnier machine in there, it's gonna have wiggle room at the sides which could either break the usb C male port in the base of the dock or could damage the Switch lite by falling forwards inside the dock.... also... there is a reason other than cooling it can't go in there

Look at the analogue sticks of the original model inside the dock, the stick is about .5cm away from the edge of the dock.

Now picture that Switch in the same dock, those sticks just aren't far enough apart to slot in there, compounded by the fact that they're not removable like in the original unit. But looking at the size differences I'm not sure could you slide the Switch lite into that dock with the sticks placed where they are, I think even with a perfectly central usbc connection the system wouldn't fit in there.