The thing with plastic liners and grease is that the friction is increased if the grease contains any of the usual metallic EP (extreme-pressure) additives.
Even bearing greases often described as being "Teflon-fortified" likely contain the EP additives, since Teflon isn't nearly as extreme-pressure as the metallic additives are.

These additives prevent galling between metal surfaces where high-pressure contact is expected to occur, where hardened steel is usually used.

I'm surprised that lined-housing-specific lubricants aren't commonly sold, though various lubes don't contain any metallic additives.

Shimano's premium SP-41 and newer housings are pre-lubed (nowadays along their entire length) with a silicone-based lube developed (and hyped) for use 10-speed shifters, and many cable kits are sold that I presume are intended to run dry(?).

Lithium-based petro grease is great for un-lined housings, but relatively poor for plastic-lined ones.

The GripShift lube is so viscous it mustn't be pumped into a housing or will cause sluggish motion, but used somewhat sparingly on the inner wire it is like magic and will never gum up from years of storage like petro greases usually do.

Most lubes work well enough to be acceptable in any kind of housing, but best performance from the cabling requires cleanliness and an optimal lube.

And I am leery of any kind of grinding to the ends of housings, basically I don't do it.
The dust from a grinder or the filings can and will be dragged in and embed in the plastic liner, making it perform more like old cabling.
Brake housing can be cut sufficiently square with a bit of practice nipping the coil just right, giving a solid feel at the lever if all the housings are settled in during installation (especially up inside aero-style brake levers).

Gear housing is intended to be cut with wires left sharp, allowing the ends to embed in the plastic ferrule so that the compression force is more-evenly distributed among the lengthwise wires after the housing is bent into a curve during installation.
Even metal gear-housing ferrules have a plastic ring inside to facilitate the embedding and stress distribution, and filing the ends square totally blunts the wire's ends to the point where this settling may occur later during the service interval instead of during the setup pre-stressing.