For now, check this out:
1/ Test : spritesSDL displayed 9 framesSFML displayed 303 frames--> SFML is 3366% faster than SDL2/ Test : alpha-blended spritesSDL displayed 5 framesSFML displayed 216 frames--> SFML is 4320% faster than SDL3/ Test : rotating spritesSDL displayed 3 framesSFML displayed 277 frames--> SFML is 9233% faster than SDL4/ Test : static textSDL displayed 416 framesSFML displayed 6092 frames--> SFML is 1464% faster than SDL5/ Test : dynamic textSDL displayed 363 framesSFML displayed 948 frames--> SFML is 261% faster than SDL