My view of it was that there was an initial decent sized-booing when he was subbed off, which gave way to a decent sied applause (that was perhaps as much in response to the boos as it was to Bissouma).
I dunno, whenever anyone brings up Bissouma being on the bench as if he should regret going, I just look at our bench and see Undav, Mitoma, Colwill, Gilmour sat there not getting starts (and in some cases, not getting on the pitch).