Does this car see lots of short trips / engine starts - stops? I've seen lots of Euro engines ( VW for example ) not tolerate this very well.

If the lash adjuster / hydraulic compensator / "lifter " is a hydraulic cylinder with a check valve at the bottom. Oil pressure extends the hyd cylinder to take up clearance and ,when the cam presses on the rocker, the check valve closes allowing the system to go solid.

The post above speaks of different thickness lash caps, this is done to keep the hyd cylinder in mid travel, if the cyl is fully extended, you may get valve noise, If the cyl is fully collapsed, a engine valve may stay open.

Somewhere in the shop manual there will be a measuring procedure.

The other question is , if there was no noise prior, why were the parts changed?