4GB on a gaming card in 2020 is just not acceptable. The minimum should be 6GB by today standards.
That goes for Nvidia's competing GTX 1650 SUPER that they just launched a few weeks back as well, and unlike the 5500XT, that card doesn't even offer a higher VRAM variant. The 5500XT does offer an 8GB version though, even if it's arguably a bit overpriced at launch. As was said though, lowering texture detail a bit in the most demanding titles is likely to prevent performance issues, and those primarily interested in slightly older games or esports titles might not care enough about additional VRAM to pay an extra $20-$30 for it. There are some rumors that the 5600 might come in 6 and 8GB variants, rather than 4 and 8GB, though that should be expected, seeing as it will likely be priced closer to $250 at launch.
There most propably Are not a lot of 5500 chips... instead there Are a lot of polaris still available. Amd would make Suiside by releasing 5500 at cheaper price at this moment.
Yep, though it does kind of make me wonder why they even bothered releasing the 5500 XT at this point. If anything, they should have focused on getting the 5600/5600XT out as soon as possible, since they haven't had any cards worth getting in the $200-$300+ price range all year. There's around a $150 price gap in their lineup between the RX 580/590 and the RX 5700, and the only cards worth considering in that range have been the GTX 1660, 1660 SUPER and 1660 Ti. It seems a bit silly to release another card in between the RX 580 and 590, when those cards already perform within 10% of one another.
Either way, the price of the RX 580 and 590 will need to drop further. The 1650 SUPER typically offers slightly better performance than an RX 580 for a similar or lower price, while drawing nearly half the power, so the RX 580 really needs to drop closer to $150 to compete. I guess they do still have that game bundle going on though, where one can get a copy of Borderlands 3 or Ghost Recon Breakpoint with an RX 570, 580 or 590. Now that I think of it, that just makes the 5500XT pricing even worse, since it's possible to pay a little less than the 4GB version for an RX 580 with 8GB of VRAM and a bundled game. That promotion will be ending within the next few weeks though, and I suspect they will probably launch a new one that includes the 5500 XT.
It is hard to determine outright "X is better than Y", though, given that in one or two games the 4GB 5500XT matches the GTX 1660. That's just weird.
It's not really weird. AMD and Nvidia's cards use different architectures, both with their own strengths and weaknesses, and it's always been the case that some games will perform significantly better on one or the other. See this performance summary from when the RX 580 launched, for example, comparing it to the GTX 1060 6GB...
https://www.techspot.com/review/1393-radeon-rx-580-vs-geforce-gtx-1060/page8.html
The average performance across the games tested is very similar overall, with just a couple percent separating the two, but if you scroll down to the chart comparing average frame rates in each game, you'll notice that the RX 580 performed up to 18% faster in some titles, while the GTX 1060 performed up to 14% faster others. That's why it's good to test as wide a selection of games as possible for reviews, since a few outliers could potentially make one card look notably better than another. With new cards or games, it's also often the case that there will be performance anomalies that get addressed post-launch.