Absolutely. Aerospace 303 on the cover. Spray on liberally. Work in with a paint brush. Leave over night to soak in.
Use masking tape to keep polishes away from surfaces you don’t want polished. The residue will not come off rubber or plastics as a rule of thumb. (Exceptions occur)
So mask off plastics and seals before polishing.
The water marks will be etched into the paint and alloy. Rain won’t be so bad, unless you live somewhere where industrial residues can settle on the cars surfaces. Then rain can dilute the residues and become acidic and etch the paint and metal.
I live in Perth and the scheme water is very alkaline and mineral rich. It will etch just from washing the car and not drying it quick enough. I spent two days getting the windscreen polished back.
Maguiars Glass polish. Not even 0000 grade steel wool worked on the glass.
As for your plastic trim, I would escalate the issue. Go higher.
You can polish the alloy, but protect it after with a wax at a minimum.
For detailers, the over finish will be corrected. A measure of paint thickness followed by compound finishing. Then polishing. Then a sealant. The preferred sealant would be a ceramic coating. Like a layer of glass. These are what offer long term protection but require a degree of skill to apply.
You can use Turtle Wax Hybrid Ceramic from SuperCrap or Autobarn. Maguiars do a version, but it’s hard to work with. Mother’s do one and I find it hard to get a good finish with it.
If you want this to remain tip top, I’d suggest at least paying a detailer to give it a once over. This will cost but for $600-$800 it will look better than new and be protected from etching for a very long time. Then after that, it’s a simple maintenance detail every now and then.
Have a browse of some of these. Sandro is one of the best out there in Australia and is super good at teaching (which he does as well) people to be better detailers.
https://youtube.com/playlist?list=PLr3U57CH2CtUkJ9HsDdjvMNPMXQJhGEcP