It's not bad. The form actually says you don't have to calculate your tax and you can leave the remaining fields blank. The IRS will crunch the numbers and send a bill/refund. If your income is simple, that's a good way to file. If you made a mistake crunching that part yourself, they will correct it. If you get a refund or don't owe much, then it's not a big deal.

If you have choices (e.g. joint vs separate, itemized vs std deductible), then you want to crunch the numbers yourself so that you can make the best choice. You also need to be careful if you have reporting requirements that don't affect the tax total that year like IRA backdoors and AMT books.