Traditionally most airless paint sprayers are supplied equipped with a quarter inch internal diameter airless paint spray hose.
This size airless paint spray hose is almost always more than adequate. So most airless spray painting applications especially when the fluid port sizes in the airless spray gun and the airless spray pump are compared. Fluid passageways in most airless spray guns are usually much smaller than quarter inch internal diameter paint spray hose.
Another consideration is the actual airless spray tip size typically measured in thousands of an inch even the largest airless spray tip sizes do not even approach 1/10th of an inch so at face value it does not seem to make any sense that airless spray tip hoses with larger internal diameters are needed.
Larger internal diameter airless paint spray hoses do contribute to a lot more volume of pressurised fluid being present in the airless spray system simply because of the larger hose volume but whether this will be an advantage to your airless paint spray application may be debatable.
One highly probable benefit of large internal diameter airless paint sprayer hoses will be the increased volumetric expansion capability of the hose. A practical way to demonstrate this is to pressurise an airless spray pump up to a set pressure and then switch the machine off. Carefully and slowly open the airless spray gun while directing the outlet into a measuring container. The total volume that is measured will indicate the amount the airless spray hose has stretched under pressure. Now fit a different internal diameter airless spray hose to the airless pump and run the same test again and the difference in volume bled off will indicate that particular airless spray hose expansion properties.
A will benefit of an airless spray hose with greater volumetric expansion properties is the airless spray hose is pulsation dampening. Greater pulsation dampening properties contribute to higher quality airless spray fan patterns and much more consistent paint atomisation.
A further possible but yet debatable benefit of a larger internal diameter airless paint spray hoses may be a reduction in friction over long hose runs. Typically, I have observed 100 percent solids solventless coatings being sprayed many many times in the past through one quarter inch internal diameter airless paint spray hose over 90 metres with no noticeable pressure drop at the airless spray gun.
On the other hand, I have observed many times in the past how a larger internal diameter airless paint spray hose fitted to an airless sprayer has been instrumental in reducing pulsation at the airless spray gun.