Bitcoin can be massively adopted only when it would have some price stability.
No chance we'll see people spending lot of their bitcoins because they hope it's value will rise and no chance we'll see merchants massively accepting bitcoins when there is a constant fear of bubble and crash.
It's simple as that, some tech internet companies might adapt it but until bitcoins stop to be hugely speculative stuff there'll be no mass adoption.
How do you define mass adoption? People spending their BTC? Or people hoarding their BTC? Still mass adoption of the coin either way. And as all the data suggests do to bank account confiscations and precious metal confiscations now occurring in Europe there is a flood of people adopting BTC.
I define it the mass adoption as OP said it - paying pizza with it, pizzerias paying suppliers, they paying their suppliers etc..
No chance those kind of businesses are going to massively adapt bitcoins unless it's tied with fiat value. Supplier doesn't want to sell his good to pizzeria just to find that bitcoin went 15% down while he was driving back what would eat all his profit on that transaction.
they can all use bitpay and secure their earning in USD at the time of the TX, wont make a difference, its still going to snowball!
"good money drives out bad money" or something like that...