Installation is pretty easy if you choose the Xfce version. The system is stable but many things in it (such as the init system) are unpopular which makes the learning curve very steep. The repo doesn't have that many packages so you have to rely on Flatpak (or Snap but idk if it works on Void) for software support. Hardware support and drivers may be an issue because of that as well.
I can only say "good luck". It is not an easy distro. Though if the apps you use are available as flatpaks, you may be fine.
Void is getting some attention recently. Nice.
I hope so.
Really good setup. 10/10 distro choice as well. But I have a question. Does Invidious still work for you? For me it always gives a "Video is unavailable" or a "This helps protect our community" error.
But there should at least be a way to prohibit them to share the data with third parties.
I never trusted it because I thought it was completely proprietary. Well now I know it basically is.
What language do you have set on your system and what terminal are you using?
Well if you recommend getting an older phone because it's cheaper, GrapheneOS support may be a concern. Also I think a phone usually can last for 7 years with 1 battery replacement, good ambient temperature and careful use.
I only know 2 good providers: Proton and Tuta.
I think 4GB is plenty for web browsing if there are not many tabs opened. Though the laptop will still be slow because of the specs.