Adoption by banks is already underway. Maybe they won't hold crypto for customers (at the moment) but custody of these assets will take place soon because of competition. Besides the many side chain projects invested in by global finance, logistics, energy, trade and so on. In my humble opinion the financial world is focussing on the flow of value rather the old custodian practices we know of banks, they already know how to take care of that part and have available the biggest lobbies (over multiple sectors). They own the place. They will offer (payed) services initially it looks like. Mostly for current and new big accounts it seems (depending on region etc.)
[Nexo.io](http://Nexo.io) is an example of a England/Swiss based bank offering custody (Goldman S. backed) and lending services for almost 4 years now. The SBI group, Goldman Sachs, R3 consortium and so on are already years underway preparing for the 'right' moment. While doing key strategic investments and creating joint ventures.
There are other (DeFi) platforms with coins like Lend/Cel/Atom
There is still a long way to go but custody/lending is already a use case and the DeFi world will create additional inflow into the crypto market. High compounding daily interest and low lending rates are attractive and attracting new players fast.
Bullish signs everywhere for traders and the confirmation for those who see the true potential of these assets holding (and/or trading :) for a long time. There are very little assets in the world available having more than one 'potential' use cases. These coins have features still unknown and are real utility coins besides fun and fake coins money attracts. And even those can become useful or popular creating value on the go.
From another perspective. The dollar / US needs the blockchain-/crypto sphere to solve the debt problem. It's their only solution it seems besides drowning their citizens and I never met a cheap US president for decades, debt will probably rise until ...?
Assets (think anything of value people want to invest/speculate in) will increasingly becoming more liquid not only because the masses gain access to them (even micro parts) through digital assets. They are simultaneously speculated on and will be accumulated by stakeholders for whatever function. Mostly without user interference and even automated smart contracts contributing while you concern yourself with other things. Settlements will be verified instantly, your money freed up faster than ever.
That last part of 'winning' time will create additional value, a lot of it. You can spend a dollar, receive an item, sell it within a short time and so on across borders with any currency in mind. With little effort you can circulate your money infinitely and this effect will generate enormous liquidity for those touching the flows of world wealth.
These points alone can evaporate the US and global debts from my point of view or at least take away most of the pressure. Something rarely touched upon by the experts in finance besides CEO's and global fora. This narrative will become mainstream eventually if things move forward as suggested. If (/when) crypto adoption takes place you can bet on redistribution of global wealth magnifying that wealth and those left behind will never catch up again, this leap will be giant whether you like it or not and banking will claim their stake. A not so popular view I believe.