Cook the fettuccine in a large pot of salted boiling water according to package instructions; drain and keep hot.
Heat 1 tablespoon olive oil in a large skillet over medium heat, add the minced garlic and all the spinach, and cook, stirring, until the spinach is wilted; transfer to a bowl and keep warm.
Add the remaining 1 tablespoon olive oil to the skillet and heat over medium-high; add the drained artichoke hearts and cook, shaking or stirring occasionally, until lightly browned and heated through; remove and keep with the spinach.
Return the skillet to medium heat, add the butter and softened cream cheese, and whisk until smooth and combined.
Slowly whisk in the heavy cream, then add the grated Parmesan, salt, black pepper, and a pinch of red pepper flakes; stir until the sauce is smooth and slightly thickened.
Stir the cooked spinach and browned artichokes into the Alfredo sauce until evenly combined.
Toss the hot fettuccine with the sauce, plate, and top with the diced tomato and extra Parmesan if desired; serve immediately.