a speculative scheme that depends on unstable factors that the planner cannot control;
"Internet bubble" refers specifically to the time in the late 1990's when optimistic and unrealistic ideas led people to invest speculatively in the internet. Much of the money was spent establishing websites. When it turned out that there was no way to make these profitable, many people lost money. This is also sometimes called the "dot-com bubble".
A bubble "in the making" is one that is developing, being created at the moment the writer speaks of.