What is happening right now is going to push other countries away from a centralised global financial system.
Freezing of central bank assets is actually quite a huge move because other states are prevent Russia from using their own money. This is technically not theft but technically their obligation towards Russia has been breached. Other countries might not view their reserves secured if they are parked in countries who may not be friendly in 10-20 years (Saudi Arabia for example is looking very cautiously). This of course is pushing other non-west aligned countries away from west dominated financial structure.
This conflict is in reality will help accelerate a development of new world order. Globalisation is going to wane. Previously the US dominated economically and it made sense for it to be the reserve currency. USD role as the reserve currency was already decreasing for the last 20 years and the current developments and sanctions will only accelerate the natural decline of the US influence as other major economies strengthen (in particular China and later on India).
But do not misunderstand, USD losing status as the world reserve currency is not going to destroy the US and it will not be a specific point of time with an announcement (unless we have another Bretton Woods).
What is happening right now is truly profound as it is showing that our global financial system and security systems have failed. I am very curious what new system will emerge but we already have foundations for it but I am guessing it is likely to park itself into a bipolar world as opposed to a multipolar world (until India matures) where we will have two parallel systems, one based on the US and west and other system based on China and those who do not align itself with the west.
As for reserve currencies, it will be a basket of various currencies as has been the case for the last 30 years, with US share of that basket decreasing all the way to a reasonable proportion to the share of the world economy, as it should be.