If Bitcoin becomes widespread enough that most people hold their savings in it, then it will greatly and permanently reduce liquidity in the financial system, lead to a decrease consumer spending and cause major ructions in the global economy.
what you dont realise is the M0 and M1 money that circulates in peoples daily spending is only a few percent of all "money" locked up in different schemes already.. so it wont lock up peoples m0 and m1 money any differently than current schemes
however people will move from investing in stocks and shares to ALSO invest part of their long term m3 money into bitcoin so will reduce the amount locked up in traditional financial investment schemes
also to note..
when people buy bitcoin. there is no lock up of that cash.. the market cap is not a reserve of money.. its instead just math of taking the current market price and multiplying it.. its just a empty number of math not an allotment of cash locked up.. when someone buys bitcoin, someone else equally sells bitcoin and so the money still circulates by the bitcoin seller receiving cash and then him using that cash in traditional spending ways circulating it normally
when money is truly "locked up" its usually in insurance policies or where pension deposits buy shares and then those shares invest in other things and the circulation of M3 is just bouncing around in the tradfi stock/share/insurance/credit markets
only some of that will come out of the m3 and move into bitcoin and then the sellers either move it into m0 m1 or.. or.. m3 again
..
remember and emphasis this
when buying bitcoin you are not locking your money up into a vault or reserve, the money does not sit around waiting for you. you are instead buying a currency from a sell and that seller is selling bitcoin to get your money to then have them use your money on their personal choices of how they want to spend their money
that money can just circulate in m0 m1 circulation or end up back in m3 investments of tradfi