there is a small charge in water molecules that strongly attracts cations to the oxygen atom and anions to the hydrogen atoms. there needs to be a ton of energy spent to move the ion away from surrounding water molecules into the uncharged hydrocarbon tails in lipid bilayer. It is extremely unlikely for ions to pass through lipid bilayer instead of going through ion channel.
an ion’s water shell contributes to ion channel selectivity
references
Kandel, E. R., Koester, J., Mack, S., & Siegelbaum, S. (Eds.). (2021). Principles of neural science (Sixth edition). McGraw Hill.