These are periods that all teams go through, see Real Madrid, or Barcelona a few years ago.
There are no teams that are free from problems, even Manchester United, who were at the top years ago and are now floating in the middle of the table.
I am sure that Inter will rise from its ashes.
In my personal opinion one of the problems that Inter had last season was that they did not make significant enough transfers to regenerate their squad. I don't know if the club owner was very difficult to spend money on the transfer market. According to one of the sports accounts on X
[1], the average age of Inter Milan players last season was around 29 or 30 years old. With that age they will have a weakness when playing against a team that applies aggressive pressure like PSG. To be honest they were also weak when playing against Barcelona. However Barcelona did not have Lewy and Kounde who were injured so both teams could score goals against each other. This is different from PSG where they have a solid defense and high pressure so that Inter Milan could be defeated by a big score in the final match.
Yes this is a problem that Inter Milan must face. If they were still with the same team I think they might even be out of the Serie A title race or be eliminated in the early rounds of the UCL this season.
[1].
https://x.com/TheAthleticFC/status/1928881200245997682