Tottenham have never been close to relegation like all other clubs in the Premier League since the bottom three Leicester, Ipswich, Southampton immediately took the last three places and they were always too far from the rest of the teams. As for the Tottenham trophy, it is mostly due to the new format of the competition, I think the difference in the average strength of the teams of previous years and this season is obvious. And considering the number of teams currently participating in the Champions League (for example, 6 from the Premier League haha), the quality of the Europa League will not improve.
UEFA doesn't want to improve Europa League or even Conference League. In fact the new format was to collect more money and make new teams in these two competitions win titles rather than the classical teams. There is a positive points is to boost the funds of the teams participating in these competitions and help them improving the squad so a long term improvement in the quality of teams especially from lower leagues in Europe. Obviously in short term no direct benefit will be seen.