1660ti does 507 H/s with XMR and 30+ MH/s using 60-70 watts for Ethash.
Even if it does that, a rx 570 can be bought for $100 and the 1660ti is around $350. What the hell.
The 1660 is $220.
The 1660ti is $279.
Avoid bullshit variants or paying for markup.
A 2060 is $350.
A P106-100 is around $100 if you are looking for cheap used GPUs.
There isn't a point in mining ETH right now, better off mining another coin and exchanging it into ETH if you want to accumulate it.
If you really only want to mine XMR; sure get an AMD GPU.
You talk as if there is a choice for amd miners. Every website says eth still the most profitable popular coin using amd gpus. Now if you say nvidia users then I agree with you and already posted many times if mining with a nvidia gpu then there is no point even thinking about eth but the funny thing is you posted the 1660ti hashrate for xmr and eth as it made any sense using it to mine them.
And by the way saying "1600 series Nvidia GPUs are significantly better than everything else. )" is also a misleading title, amd polaris still the best price performance and if you meant that is better in the sense of being better than everything else then where does the 2080ti stay? So one or the other way you are deluding yourself or the people or both with that statement.