@GerryCerryBerry
Not quite. Pleasure comes more from the pressure than the actual friction, otherwise sandpaper would be all the rage. Excessive friction leads to chafing, which leads to skin/surface breakage, pain, and possibly bleeding. Sexual endeavours (including masturbation) should always include some form of lubricant. Masturbating without lubrication can cause you to lose sensitivity in your genitals, regardless of what genitals you're working with. People tend to respond to that loss of sensitivity by adding more pressure/using more force, which eventually causes numbness.
Water based lubricants are better for internal usage, because unlike oil based ones, like coconut oil, they won't degrade or spoil overtime. Nobody is trying to end up with a UTI out here. Natural lubrication from a woman's vagina is enough sometimes, but everyone benefits from additional lubrication. Inserting into a dry vagina would feel awful for everyone involved. Forget about anal sex, where there are zero naturally occurring lubricants present. Most of the time: More lubrication = more pleasure.