True, although I would expect ripple to cause random problems, or at random times. The difficulty with replacing them right now is that this iron was supposed to be the replacement to my Aoyue 2900, which has never been great, or even good, but finally became unable to hold a temperature at all a while back. It does enthusiastically shriek about how it fails to hold a temperature, though.
A couple of attiny 4313s are on order for a brain change and firmware replacement.
In the meantime, I'll see if I can find out what ESR values those CapXons claim to have, and find replacements.
Edit:
For reference, the CapXon capacitors are:
470uF @ 50V, 13x21mm, 5mm lead spacing, GS series, spec sheet says 858mA ripple
220uF @ 16V, 8x12.5mm, 3.5mm lead spacing, the label says "SSL+", but no data sheets
Blocked by heatsink, but I think it is 100uF, definitely @ 50V, 8x12.5mm, 3.5mm lead spacing, GR series, spec sheet claims 286mA ripple!