Short answer: Before getting a crypto debit card, check identity verification, which countries are eligible, which transactions earn cashback, how refunds are treated, and what fees apply. The advertised cashback only matters if your normal spending qualifies for it.
Start with eligibility
Card products are regulated, so they require identity verification and are only offered in certain jurisdictions. Check the list of supported countries and what documents are required before you plan around the card.
A product that is not available where you live, or whose verification you cannot complete, is irrelevant no matter how good the headline rate looks.
Read what counts as eligible spend
Cashback programs usually exclude some categories. In a past ether.fi promotion, cash advances and ATM withdrawals did not count, and returned purchases reduced the eligible spend and therefore the reward. The current terms may differ, but the pattern is common across card programs.
Look at your own spending: if most of it falls into excluded categories, the effective cashback is much lower than the advertised one.
Compare the net result
Cashback is one line in the calculation. Add any card fees, foreign-exchange spreads and the cost of converting your crypto into spendable balance, and consider whether spending an asset you expect to appreciate is a good trade-off for you.
A simple test is to total a typical month of spending and compute the net benefit after all costs, using the terms in the app rather than the marketing page.