Opening Necrozma Prism Tin [Dusk Mane Necrozma GX] returns about $29.49 in card value against its $224.99 price — roughly $0.13 back per dollar spent. On current prices, you lose money on average by opening it.
See every card and pull rate in SM - Ultra Prism
How expected value is calculated — card value only, from published pull rates and daily market prices.