They have definitely found their way back into higher quality soccer that they are usually able to play. The beginning of the season was a horror for them and if you have a start like that the confidence is also starting to shrink from one game to the next.
Yes, thankfully they found their way back so well that they seem to be able to make an epic comeback before it's too late. And of course they won the European league, isn't this a pretty drastic progress for them. However, next season is always waiting, whether they can really rise and become big again or not, because of course there will be many more challenges. And they have to find good players again who are suitable to be able to rise.
Sevilla used to be a very strong team some seasons ago and they have been widely known across Europ for their European league title wins. Even when they qualify for champions league, they technically drop back to European and they definitely win.
With this recent succes, and for the fact that they are playing in the Champions League, I believe they are back to the success and winning track such next season, as we mention Barcelona, Real Madrid, they will surely be next.
To say they will experience success, I still can't say that, because they still have a lot to improve. Their performance in La Liga and Europa League is like a gap, I think we are all aware of that. In the domestic league they stumbled and struggled to get to the top, but in the European League they were very successful and they even won the championship and that was not luck because the game also went as expected in the European League.