Unfortunately site designers who used to count every kilobyte to save
time on downloads now think nothing of multi-megabyte pages (with bits
included from multiple sites with layers of indirection so that a
browser has to load and execute one piece before fetching the next). And
browsers themselves have become bloated. It's not uncommon for a single
page to consume tens of megabytes and a full set of windows and tabs to
consume gigabytes (in which case RAM does indeed become a measure of
speed again as swapping starts).
Network speed is a big part of the equation, but not the only part.
paul