I have pretty much the same type of machine, and while it's true browsers are hevier than they used to be, I suspect it's the rest of the software on your machi

I have pretty much the same type of machine, and while it's true browsers are hevier than they used to be, I suspect it's the rest of the software on your machine consuming too many resources to leave anything for the browser... With my x session and window manager my machine only uses about 300MiB RAM, browsing is not unlike using a modern machine. If you are using a big DE consider switching to something lighter and you might be surprised how little RAM you can use. (My anecdote is from using both Chromium, FireFox and qutebrowser more recently - I haven't noticed much performance difference in the latter but it wasn't struggling to beggin with)