I have no clue whether an S10+'s Snapdragon is equal to whatever CPU is in a base model PS4. The RAM looks fine at 8 - 12 GB. Current prices have that phone listed for $1000 on both Amazon and Best Buy though. So, even if an S10+ really were as powerful as a base model PS4, there would still be a ridiculous price gap. Or are consumers so idiotic that they will gladly pay a grand for a phone over four or five years of payments?
Snapdragon 855 should beat an 8-core Jaguar by a sizable margin.
Bandwidth is where things fall short though... The 855 will only offer about 34.13GB/s of bandwidth, which is going to limit it's gaming capabilities, especially at higher resolutions that the Playstation 4 will target.
GPU wise the Adreno is surprisingly capable and extremely efficient, more so than AMD's ageing Graphics Core Next architecture... But at the end of the day, the Playstation 4 has a sheer larger number of functional units which means it should win in every scenario.
Now when comparing Snapdragon against the Xbox One, things start to lean towards the Snapdragon a little more, but the Xbox One should still hold a slight edge in the GPU/Bandwidth department.