I would say yes. I have never used a pure sinewave UPS outside of a data center situation and all of those are on-line units as opposed to line-interactive anyway. I have personally never seen an issue with stepped sine UPS units on typical pro/consumer workloads.

lots of small and mid sized shoestring budget deployments make use of “economical” (but name brand) UPS units on legit sensitive equipment without fuss.

edit to add: of course, if your mains supply is absolute garbage, then a better quality can make a difference. if utility is clean and the UPS will just be doing ocassional brown/black out duty, then I would not spend more on a sinewave UPS.

performance metrics for power supplies (a PSU as opposed to a UPS) are calculated using the regional AC sine. anything other than a pure sine is going to make the connected PSU work harder and, eventually, marginal components may fail.

having said that, stepped square, modified square, simulated sine are generally going to be perfectly fine for virtually any consumer equipment you connect to it.

cyberpower make cheap (but halfway decent) UPS units. I have used both APC and cyberpower for years without issue.