Who is "they"?
However this ignores the reality that they can already not buy any useful amount of bitcoins with their currency and mining is unrealistic.
Maybe some altcoin might work, but then a lot of vendors would need to switch as well.
The people could individually decide to switch to cryptocurrencies (or dollars, euros, bottle caps etc...) and get others to accept it but then you have the problem of purchasing this currency in the first place and it still doesn't solve the underlying issue of the broken Venezuelan economy. You could be a bitcoin billionaire in Caracas right now, if the shop doesn't sell toilet paper then it doesn't sell toilet paper. On the other hand if you have bolivar bills...
It's not the bolivar that's broken, it's the Venezuelan economy. This ridiculous inflation is a symptom.
When governments fail to protect the private property rights of their citizens, be it physical property, financial investments and savings, to the income they earn, poverty will result for the majority.
Lack of protection for the private property probably didn't help but making that the main cause for the Venezuelan collapse is a very ideological stance to have IMO. Insert here the obligatory "look at china" counter-example.
As far as I can tell the only way to really avoid this catastrophe would've been to diversify the Venezuelan economy in decades past (something Chavez promised to do but didn't) but nobody did it, regardless of political affiliation. "Free money coming straight from the ground" is just so much easier for a politician than making a complex and potentially impopular long term economic reform.
China has a state plan and they invest in businesses. That means they provide resources to businesses instead of taking them away. Maybe that sounds like just better implemented socialism. Or maybe it's just literal capitalism on a scale never before seen. Think about it. What does the government of China provide to its citizens? If you are poor in China, will the government take care of you? No. It might provide you with a job, though. The USA is more socialist than China, the government will provide food, housing and even medical care for you and your children. You cannot be refused from an emergency room because you cannot pay. A few extremely wealthy people run China, and make decisions that are in their best interests. They invest their capital to get returns. Sounds like capitalism to me.
I'm pretty certain that if the right had been in charge when the crisis happened things would've played out mostly the same (I don't believe for a second that the right would have better diversified the economy for the same reason that the socialists didn't, nobody says no to free money), the main difference being that they would have cut all the benefits to the poor immediately to cushion the fall a bit and they'd have let papa USA bail them out in exchange for a de-facto feudalization of their economy. I agree that it would probably have turned better for the Venezuelan people (at least in the short term) but socialism vs. capitalism is not really the cause of the crash, it's more about the recovery or lack thereof. If the petrol infusion had kept going I'm sure people would be chanting Dear Leader's name in the streets, whoever that would be.
If I'm correct, I'd say "they" refers to "Venezuelans", that is, the inhabitants of Venezuela.