There are many ways, the most common is to lend your stablecoins against collateral crypto. So if you put 1000 USD in the lending pool you have let's say the guarantee 2500 USD worth of bitcoin are serving as collateral. That will get you about 5% on a serious protocol.

You can also provide liquidity on a stable stablecoin/stablecoin pair on a reputable decentralized exchange and get some of the fees.

There are surely many other "safe" ways.

If you live in Switzerland you're probably not gonna bother but it is more transparent and safer than than what a lot of people have access to around the world.

I know the DAI stablecoin was already very popular as a saving account in Argentina around 2018-2019.