Since you are sharing anecdotes, let me join.
For me FF has always been extremely stable, and I too regularly keep 100+ tabs open, on much more limited system resources. It is so stable that I’ve completely disabled history saving, and if there is something I want to read later I just keep the tab open. Never had an issue.
Tree Style Tabs also pushed me to have many tabs, because now I can actually organize those that I’ve opened and find them later.
Mandatory link to Rhabarberbarbara