Love this haha
Had quite the head-to-head fight with a clan member that tells me I don't know what I'm talking about, the 5070 will be able to do 4K without issues, sure, but turn off the software magic and tell me how it performs when it comes to raw power. I think he's pissed off, haven't seen or heard anything from him again.
Anyway, back to OP's query, as mentioned by several others, agreed, the viable upgrade for 1440p, would be a nice secondhand 4070, heck the Ti would suffice for years to come. That said if you don't upgrade to 4K
Don't go down the route I did, my 3080 was amazing for years, 1440p all day everyday.
Then I found a sweet deal on a 32" 4K monitor.... yeah... that 3080 at 4K wasn't feeling it anymore.
Once those 5000 series cards drop in stores, I'm pretty sure on Carbs you'd find a few 4070's at decent prices, they'll be gauging the market though, so a few gents might be asking high prices for some time, but keep your eyes out, there's a bargain here and there.