As for funding: https://techcrunch.com/2018/08/04/boston-area-startups-are-o...
I don't think Boston is as much as a slouch as you think, in fact it's is pretty well positioned for the long term in regards to overall industry diversity and pretty respectable funding (though not as dominated by software like SF might be)
Salaries are probably lower because overall COL has traditionally been lower here (though housing sure isn't far behind anymore). Most people I know working for the big companies are getting ~$250k total comp (8-10 years exp). Other large, if more under the radar, companies are not too far behind.