Generally, capacitors don't short to ground. They do! But not very often. Bit it is true that it becomes more likely with age/use..like any cap failure...Maybe like once a year I'll find one ruining the bias on a radio, and I work on alotta radios...I run into open and bad esr alot more often...condensers are just caps anyway
It depends on the manufacturing method....for instance, old Bosch condensers were paper/foil. I was told that some old Delcos were mica! Bad juju those get silver migration and get real leaky.
Most aren't electrolytic caps, which short more often. More than paper on foil anyway....which still do! Or hell, maybe I'm wrong and they are electrolytic on some mopeds! Never torn one apart..hmmm
That being said, I don't even buy condensers anymore...my hobbit has been running an axial nichicon 40pf electrolytic for the past 10 years externally mounted no problems. I tried it out, it worked and never replaced it....Pays to have bins of electronic components.
If it's not a big deal to I remove the internal one, then throw on an external for ease of access. Who cares....
If the problem is the condenser, and you don't remove the old one. You'll probably be fine...but, there is always a chance it could be shorted and send you on a goose chase. Sall odds and karma