Bonjour GroundLoop!
Have toiled in power electroncis since 1970s,
1/ PFC is a benefit to the power distribution system as MW are billable and MVAR are not, the apparent power causes added heating of the conductors but is not useful work.
2/ Old systems were most resistive or inductive loads with aPFC capacitor able to correct the PF of a lagging inductive.
Since 1970s, more and more load percent is electronic, with peak charging of rectifiers causing a different type of low PF problem, with lots of harmonic currents.
The various regulatory bodies established levels of PF that vary by the type of load (eg lighting, computers) and by the wattage range.
USA, Canada, EU, CE, IEC, IEEE all have up to date specifications, which can be required for import of a device into those regions.
3/ Compliance is usually with a PFC boost preregulator.
4/ Non-compliant equipment works OK but will fail a compliance test for harmonics and PF.
5/ In large industrial connections the power distribution company will penalize the customer for excessive VARS, with a higher rate to make up for their copper losses.
6/ Finally in a 3 phase WYE system, the neutral will carry the harmonic currents and excess VARS due to heavy electronic loads can overlod and overheat the WYE distribution neutral conductor.
That can be a safety issue!
So the answers depend on the level of power, distribution system, import or export of equipment, etc.
I hope this clarifies this complicated issue.
With Kind Regards,
Bon Chance!
Jon