Smart contracts are so smart to serve developers and governments as they can use smart contracts for minting massive new tokens and dump those mint-from-thin-air with smart contract tool on the market. Smart contracts can also help governments to seize your altcoins and tokens, for example stable coins, even they are in your non custodial wallets.
Are they smart for users?
My opinion and also answer, No.
PSA: Most Stablecoins Can Be Frozen, Even in Your Own Wallets.Stablecoins and Blacklists.That depends on the smart contract code itself. If developers implement a "freeze" or "blacklist" function, it will be easy to censor addresses on the Blockchain. Such is the case with centralized stablecoins such as Tether (USDT) and USD Coin (USDC). Truly-decentralized stablecoins have no such feature (eg: DAI, USDJ). Not even ordinary tokens living across smart contract platforms. I'd say smart contract platforms are "smart" because they enable automated transactions and unlock the world of "decentralized finance" without the need for middleman. At least, that's how they're supposed to work. But again, developers can code smart contracts with censorship in mind. It becomes worse when the underlying blockchain platform is centralized (like Solana or Binance Smart Chain).
At least, it's possible to "fork" independent blockchain networks with ease. If the majority doesn't agree on something, they can "fork" away and move on. But I wouldn't say the same about tokens living on smart contract chains. I'd be surprised if another Bitcoin or Ethereum fork emerges. With how unpredictable crypto land is, anything's possible.