I also see Arsenal as a team that can still be quite strong next season so that some of their closest rivals last season also still have to be wary of Arsenal as their competitor in the race for the Premier League trophy. Likewise in the Champions League because Arsenal could perform better next season and be able to reach a quite crucial stage so that their rivals will still see Arsenal as an opponent that needs to be eliminated early before heading to the quite crucial stages in the Champions League.
The bottom line to go to history and record is a team don't need to be a super strong and have many impressive performances. If they have these things, they are all good but the history and records care about what are the champion team of a league in each season. Champions can be called more easily than runner-ups and value of ending one season as a runner-up is very smaller in importance and recognition than as a champion.
If anyone says Arsenal is a weak team or in other words is not a strong team, it's wrong and I can debate for proving it is wrong. Otherwise, it's not easy to say Arsenal are strong and competitive enough to win Champions League. They need to improve a lot from player quality, main players to substitutions, tactics and mentality to win Champions League. Teams like Manchester City and PSG struggled many years before only Manchester City won their first Champions League title two seasons ago while PSG are still fighting for their first title.