I think this was really a hangover from the avgas days where there was less bulk fuel control and the engines were less tolerant of water.
The early jet engines did suffer from water particularly with it freezing in filters ( ala RR Dart.)
The control of tank farms and tankers has greatly improved so reduced the likelihood of contamination.
Engine design with efficient Fuel/oil heat exchangers and tank design with scavenging and jet pump systems have all removed the contamination problem from a day to day noperationional point of view.
The main problem now is a fungus (cladisporum)which attacks the metal fuel tanks. This fungus lives on the water both laying in tanks and water that is absorbed into the fuel naturally. This is now treated on maintenance checks with the use of an anti-fungicide ( Biobor)