Liverpool are expected to strengthen their squad next season. Next season, Liverpool, City and Arsenal will probably fight for the title again. However, if the performance of Chelsea and Manchester United improved, the Premier League would become more competitive. These two teams are far behind.
You have a point Manchester United and Chelsea are far behind compared to how they were few years back. Chelsea have shown some sign of improvement towards the end of the past season and if not because they Sacked Pochettino Chelsea should be able to challenge for the title as well because they have been gaining back confidence and their balance.
Next season the competition might not be as exciting because even if Arsenal still try to win the title we all know they won’t be able to win it unless Guardiola leaves Manchester City. Manchester City might see less competition because Kloop have left Liverpool and they’d probably lose more players and it might take time for the new coach to adapt to the league and the players.