He is getting closed down by 2 players most games because teams know he is the only attacker who can maybe do something. Even the Brentford manager spoke about it in his post match interview.Kudus isn't getting worse; he was never any good. He's a poor player, with bad conditioning. His first touch is dreadful, and out of possession he is a ball watcher. He is essential everything that Adama Traore was - and as Tim Sherwood put it best, he's got talent, but his head is full of rocks.
Muani is at Spurs because nobody else wanted him. Clearly a reason why PSG abandoned a 90m striker so quickly. He's playing for a pay check; and will turn it on when it suits him, not the club.