Imagine that, football evolving & not playing with half backs & inside forwards anymoreYou are confusing signing a striker and strengthening the squad.
If you just accept we play without a striker, and instead play with a front 5 who can largely interchange, its pretty obvious that adding a £100m player like Grealish (who was one of the best players in the league last year.) Is strengthening the side.
You can put our front 5 of Sterling, Grealish, Foden, Mahrez, Torres, KDB and Gundogan up against the attack of anyone in the league and it will score more goals.