not only alcaraz, sometimes sinner is unreal too. if we didn't have athletes like djokovic and nadal (and murray too before his injuries killed his career at the top) i'd say they took tennis to a new level.
the big 4 (big 3?) took too long to replace because the youngsters couldn't reach their mental, physical and technical level. nice to see finally some continuity at the top. alcaraz and sinner are there both technically and physically, and as good as they can be at their age mentally too