If you are looking to buy one new right now, I agree with WildCard's suggestion that it's not the best value option at the moment, at least when going by current US online pricing. Most 1050 Ti's are priced around $170 or more, which is arguably way too much for the level of performance they provide relative to other cards, and is even higher than what the card launched for two-and-a-half years ago. The 1050 Ti was an alright option a year or so back when there was a graphics card shortage that caused the prices of cards to rise significantly, but prices have since come down, making it a much less attractive option.
The Radeon RX 570, by comparison, is around 50% faster on average, and is widely available for less, with a few models even priced under $130 new. Or for about the same price as a 1050 Ti, you can get an RX 580, which is even faster still. The only real downside to those options is that they require greater power draw under load, so your system should have a relatively decent power supply of around 500 watts or so. The 1050 Ti is more efficient by comparison, allowing it to run on most lower-capacity PSUs, like those that come with many pre-built systems.
However, even if you have a low-end PSU and don't want to replace it, there's still a better option. Nvidia recently released the GTX 1650, which is faster than a 1050 Ti and generally costs less, while drawing a similar amount of power. Compared to an RX 570, the 1650 is still generally priced higher while delivering a bit less performance, but it is not as far behind in terms of value, and its low power draw could potentially make it a decent option for many prebuilt systems.
If, on the other hand, you already own one, it is still a capable card that should be able to run current games reasonably well at reduced settings. Obsolescence depends on what you want out of it. If you want to get smooth performance in the latest games at 1080p resolution with high settings, it's not likely to be adequate. If, however, you are fine with turning settings or resolution down, or are playing less-demanding games, the card may still be fine for your needs.