Arsenal is still in the title race it's still very early to see their loss against Liverpool as something that will hinder them from becoming champions unless you think they will keep losing points in their coming games, Liverpool looks better than most of the teams and their squad can't be compared to that or any team in the league right now not even the Arsenal team I think it will take injuries to see them not winning the league again not even after signing Isak again.
Arsenal loss to Liverpool at the early stage of the season should not be used to judge arsenal’s performance or title race this season because everyone knows that Liverpool has a very strong squad currently and this is just the start of the season, we don not know what will happen mid season in terms of injuries and other factors that might make their squad lose it form.
Arsenal performed well in their first two matches and their starting games were all against big teams in the league, so when they start playing against mediocre teams mid season they can accumulate more points and teams that are currently playing against mediocre team will find it difficult mid season playing against top teams.