Our first three RVs had aluminum siding and our current 5th wheel has Filon siding which is fiberglass like material.
The only difference I have seen is dents. The Filon resists dents, aluminum doesn't.
Our 5th wheel is 22 years old and has never been stored indoors or covered. I wash it before every trip and wax it once every two years. When freshly waxed it looks brand new.
Our previous TT we had for 16 years. It also was never stored indoors or covered and same cleaning and waxing. It also looked brand new when waxed.
I've made modifications to all four of our RVs and each had rippled siding. The TT had deeper ripples which required good seal to make sure no leaks when mounting something to the siding or cutting a hole through the sidewall.
Can't answer the wifi question because we've only used wifi with the filon siding. But due to windows I'm not sure aluminum would be much different, plus you can always mount an outside or use an inside signal booster/antenna.