The Galaxy S10 series is still worth buying in 2020, since the phones have most of the features from the S20 (and some the S20 dropped entirely) at lower prices. Now you can get the 1TB version of the S10+ for $899.99, a $400 reduction from the usual price of $1,300. Plus, it's the full US version, not one of the dual-SIM variants with poor LTE support.
The model on sale has a Snapdragon 855 processor, 12GB RAM, 1TB of internal storage (plus a microSD card slot, if that somehow isn't enough room), a 6.4-inch curved OLED screen with HDR10+, a 4,100mAh battery, triple rear cameras, two front cameras, and IP68 water resistance. Unlike the Galaxy S20, this phone actually has a headphone jack.
As previously mentioned, the model being sold is the US unlocked variant, which means it will fully work on all major US carriers and comes with a warranty. That's a nice upgrade from the international dual-SIM versions that regularly go on sale, which lack some LTE bands and don't work at all on CDMA carriers (e.g. Sprint and Verizon).