The longer the chain becomes the slower the transaction gets. To solve that problem we use the lightening technology. This technology takes the responsibility and makes the transaction faster.
This is true but also do realize that scaling will be an ever present issue with blockchains. Once you get LN and the capacity to have transactions are raised, people will use that space instantly. Then people will say "LN is stuck and scaling issues are happening again." That is why we will never be free from this scaling debate, I implore you to forget about this and move on to something that is of real concern for Bitcoin.