Having better squad depth than Sevilla will not guarantee that Arsenal will be able to beat Sevilla easily. Sevilla playing at home will certainly get direct support from their fan base and that will raise their enthusiasm to perform better to win points. Sevilla have not won a single match in the two matches they have played, so this will also be considered an opportunity.
Of course, there is no guarantee to win against Sevilla although Arsenal has a stronger squad. However, if we learned the stats of Sevilla in UCL currently, they looked in the bad condition. So far, they never won a single match, it means they are not as strong as we expected. Although Sevilla will play at home, I'm not sure that they can steal points from Arsenal. But there should be a place for a surprise, it is not impossible if the supports from their fans to give them more motivation. If they played with big motivation, they has a chance to get a draw result at least.
Sevilla was a strong team in Europe even though they mostly failed to progress far into the next phase. I believe Sevilla will strengthen its defense and develop the most deadly counter-attack strategy to beat Arsenal.
The current Sevilla squad was no longer the same as the previous Sevilla squad. It is clearly seen in the La Liga standings, they are just a mediocre team (an average team) now. They even failed to stay in the top 10, they are only in 14th now. So, it is difficult to expect their defenders or their attackers to play as strong as when they were in their best form.