Using an RBF supported wallet is always a better option but still there are many wallets which do not allow RBF transactions
Most wallets support RBF.
At least the proper wallets. So no web wallets or other kind of custodial wallets.
Good desktop wallets (e.g. Core, Electrum, Wasabi) have the option to enable RBF. Same applies to mobile wallets.
There are many third party accelerators which are not run by mining pools but they can rebroadcast the transactions. These are useful when the transactions are dropped by mining pools. Few of them are mentioned in the article.
The standard time a transaction is being held in the mempool is 14 days.
If a transaction does not confirm within that timeframe, it probably would be wiser to create a new one with a higher fee instead of rebroadcasting it (especially if the RBF flag is not set).