Did you actually run a benchmark to see how the mystery card performs compared to an actual GT 730? As was pointed out, if it's something like a GT 545 or 550 Ti utilizing GF116, those cards would generally perform better than a real GT 730, despite being older models. Perhaps they just re-badged the card because the GT 730 is more marketable (mainly for non-gaming uses) these days.
Try running userbenchmark, for example, and share a link to the results page here...
https://www.userbenchmark.com
As for performance, it will undoubtedly be bad in many of today's demanding games, but that applies to an actual GT 730 as well, perhaps even more so, if this card happens to be faster. Realistically speaking, A GT 730 is inadequate for running something like Red Dead Redemption II. It's roughly comparable in performance to the integrated graphics included in Intel's recent CPUs from the last few years, and is well behind the integrated graphics included in some of AMD's recent processors, and some of Intel's upcoming models. Even at 720p resolution at low settings, you would be looking at somewhere around 10-15fps in RDR2 with a GT 730, likely with dips even lower in demanding areas. It was a rather low-end card when it came out 6+ years ago, and it's not going to fare too well in many recent demanding titles, even at low settings.
Personally, I would recommend saving up a bit more for something that performs significantly better, and maybe look at the used market, if necessary. Among newer cards, even relatively low-end models like an AMD RX 570, RX 580 or Nvidia GTX 1060, GTX 1650 or 1650 SUPER should offer nearly 10 times the performance of a GT 730, if not more in some titles.
Unfortunately, prices of graphics cards are really bad at the moment (at least online), due to a major shortage, and that will likely last for a number months. I wouldn't recommend paying much more than $150 USD for any of those cards I listed, but the selling prices are often significantly higher right now. Just a couple months back, you could get something like a used RX 570 for under $100, or a brand new 1650 SUPER for as little as $160, but good luck finding them near those prices now.