You don’t say which state you are in and that makes a HUGE difference.
Assuming this is NSW the colorbond roofing is def the strata responsibility but the hot water system is it a shared system or does each townhouse have their own self contained system.
The components within the house (tank) are the owners responsibility.
As their are no SBL then the roof assembly would be common (assuming individual systems) property and so the Strata would be well within it’s rights to remove them unless individual owners accepted responsibility for them.