It depends on the reason for the congestion. There are different scenarios where it can be normal or it could be a bad thing.
I can generally categorize these scenarios into 4 groups:

1. Natural congestion caused by sudden and temporary spike
These are cases where bitcoin users would send more transactions in certain time periods. For example during weekends when some big services are consolidating outputs or during market volatility times when more people are sending their bitcoins to their exchange accounts and some others are withdrawing from them.
This is normal and it doesn't last long. This is showing the natural and healthy activity in the Bitcoin world which is a good thing.

2. Natural congestion that is not going away
This has never happened before and this case is when the number of bitcoin users has grown so much that the existing capacity is no longer enough to handle all their needs. In this case we need to start thinking about increasing capacity.
This is bad if it happens and we don't already have plans for it.

3. Artificial congestion caused by "normal" spam attack
The best example is what we saw in 2017. Malicious entities fill the mempool with large number of transactions to artificially cause congestion. This is bad for bitcoin but not that bad since there is a working solution for this type of attack which is the fee market. It has prevented this type of attack well in the past by increasing the cost of the attack.

4. Congestion caused by "sophisticated" spam attacks
This is the newest form of attack and the worst type since the solution is not yet agreed upon. Specially since there are still people who don't want to admit this is a problem.
The latest example is with the codename Ordinals. In this type of attack they create an incentive for the regular users to spam the network themselves, in this case by exploiting the protocol. This is more harmful and harder to fix because for example to prevent the Ordinals attack there needs to be changes in the protocol which nobody seems to be interested in!