I remember the days of the Sydney-Melbourne, Australia 'Southern Aurora' and Melbourne-Adelaide 'The Overland' (when latter was a night train) whose twinette compartments (two berth, no sharing with strangers) always had an en suite shower and toilet. Even today's 41 year old Melbourne-Sydney-Brisbane XPTs have a toilet/shower shared between two compartments (sharing with same sex strangers can occur).
in October 2023, I travelled from Milano to Palermo (c.20 hours) and back to Roma (not the Queensland country town!) Neither had an Excelsior sleeper (from memory, that was on the Siracusa section split at Messina Centrale), but if an Excelsior compartment had been twice the cost, I would have not paid the extra Eurailpass supplement. I might consider 25 per cent on top of the fare/Eurailpass supplement for a standard sleeping compartment, but 2x is too much.
It boils down to personal preference, similar to how some who are moneyed choose three or 3.5 star hotels even when four and five star are available, but others less affluent but having the 'holiday of a lifetime' splurge.
If you'll not have showered for 24 hours before joining the train, you may want to do the latter.