If that’s just for the GPU, then it will kick some ass at 1080p.
Platform upgrade, it can still deal some damage; the main problem is that the CPU, RAM, MoBo are likely to eat more than 50% of the budget, forcing you to settle for something like the GTX 1660.
Mind it wholly depends on what kind of games you play. Some recent titles really need more powerful CPUs, but many, many others are happy with a powerful, current GPU and an old CPU.
If the latter type makes up most of your gaming diet, then you’d be good with just a GPU upgrade.