You can't predict future but very soon cash will not exist. Banks and governments will always have a control over legal adopted currenty wether you like it or not. It certainly won't be the bitcoin.
I don't see it happening by 2030 since crypto still needs time until it gets fully recognised. It will take a long time for governments to adopt it because everything moves at slow pace and there are huge interests behind all of that.
lol. you said, you can't predict the future and predicted that cash will be non-existent soon, how ironic. Well my stand on this is simple, if we are going to have a cashless society, a full cashless society then we will be needing the blockchain for transaction records and a well established stable coin completely backed by what? If it's fiat then might as well we should not do it anymore. If we are going to have the society we want, I guess it's better to backed it with something that has a intrinsic value like gold coin and bars and let the government do the regulations.
I don't know where you live but cash is getting abandoned and payments are mainly done by credit cards and through banking services. Some countries already have a plan of removing cash in the near future. Main goal is obiviously to affect black market, tax evasion, have all transactions on record and full control over someone.