The reason this line is slightly worse than the 2 Pikachu setup is that if your hand gets disrupted somehow (e.g., your opponent breaks the lock with an Escape Rope or similar, and then plays N), you now have 2 pieces you need to find from your deck (Raichu and the Devolution Spray)
Jumpstart doesnt have that luxury
While the Buster Sword is better some might call it busted The Masamune is more niche but still hugely powerful with the right deck strategy
Third, the flavor
Overall, this card is a draw engine, and if you build around it, the strategy is perfectly playable, even if it's not to most players' taste, especially as playing cards exerted can be risky against more aggressive decks
It functions well from the graveyard thanks to cards like Karmic Guide, and even functions completely under most stax effects