In the reviews I've seen of the new Ryzens, the Ryzen 5 3600x is either even, slightly ahead in a few games, or 5% behind the 8700k at the most. That's really impressive considering the price. Dollar for Dollar the new Ryzen processors can't be beaten. The performance it offers in comparison to the 8700k is too close to call and the Ryzen 5 3600x is $100 bucks cheaper.
However, what people are forgetting is that you'd only see the difference the higher clocked 9700k or 9900k makes on a 144hz monitor, and these are situations where you can actually make use of getting more than 60fps. Even with as impressive the i7 and i9 are, the new Ryzen processors aren't that far behind. The 3600x, 3700x, and 3800x are viable picks for a 144hz monitor.
The only place where the i7-9700k and i9-9900k can gain ground over Ryzen is with their overclocking capabilities. The new Ryzen processors don;t overclock worth a darn while the i7 and i9 can hit 5.0ghz if you throw enough money at them.
The GTX 1050ti is the part that's holding you back the most. You could upgrade to Ryzen and this would help to increase your maximum framerates a little, but Ryzen would do more to ease and eliminate minimum Framerate drops. Otherwise the old i5-6500 is still somewhat decent. The GTX 1050ti is an entry level card that's a good 70% to 85% slower than the GTX 1660. The GTX 1660ti is over twice as fast as the 1050ti, so getting a card like that would help you out the most.
Upgrading the the new Ryzen CPU would be beneficial but upgrading the GPU would do more to increase framerates in cases where the game isn't fully utilizing the CPU. With the GTX 1660ti you would be able to pick higher graphics quality settings.
Upgrading to the Core i7-7700k would also be a good choice since it also matches of slightly beats the new Ryzen processors. The 7700k has an all core Turbo boost speed of 4.4ghz at stock, temperature permitting. The only problem here is finding the 7700k for a good price. A year ago on ebay you could get one on the auctions for a little more than $200 but Intel's chips shortage raised the value of these old processors. You would also need a new CPU cooler like the 212 EVO for the 7700k or 8700k.
A 550w bronze power supply is good enough for cards like the RX 580 or 590, GTX 1070, GTX 1080, GTX 1660ti, RTX 2060, and RTX 2070 both regular and Super Edition.
To help fund the upgrade, you could possibly get $100 out of the i5-6500 and $30-40 out of the h170 motherboard. The GTX 1050ti is worth $80 to $100. Selling these parts would pay for 40%-50% of an upgrade to a Ryzen 5 3600 or 3600x, a b450 motherboard like the MSI with a BIOS flashback, and a new Graphics card. You can sell these parts on craigslist or offerup for free, or sell them online at places like ebay or HW Swap.