Like someone said above, as long as the flow area of the hole set is not the most restrictive orifice along the path, no problem.
On an old shop project we had to make some hydraulic filters from scratch for some old hydraulic power units that would sit outside in winter at remote sites. We went as big as possible on the inlet openings, and the housing was brazed to the baseplate (very HD). Machined baseplates were 1/2" thick HS steel, so no concerns with strength.
Big holes are better for highly viscous fluids (i.e. cold oil). If the filter mount has a 5/8" ID, even if the array of holes adds up to equal or greater than the area of the 5/8" hole, viscous oil can move more easily through that one large whole rather than 8-10-12 smaller holes. But on a combustion engine the oil doesn't stay cold for very long.
More holes will also create a weaker base plate. Therefore the thickness and metallurgy need to provide adequate strength for the pressure vessel.
