Can I travel to Pakistan with expired Pakistani passport?

Keep in mind that getting into Pakistan and getting to Pakistan are two different things.

You usually have the right to enter the country as a citizen. (This is true for a lot of countries.) However, it could be a little more difficult and time-consuming to prove your citizenship to the border official if you do not have a valid passport.

It will be difficult to travel to Pakistan, though. No airline will let you board the flight if your passport is not valid. You do have the right to enter Pakistan as a citizen of Pakistan, but the airline cannot confirm this without a valid passport, so they will play it safe and refuse you boarding. If you are refused entry, they will have to pay for your return flight and pay a fine.

You will never have the opportunity to present your case to a human being because they actually employ an automatic system for those inspections. (Or more accurately, the automatic mechanism cannot be overridden by any human being to whom you could argue your case.)

In other words, even though you are technically able to enter Pakistan, you are unable to do so, so you will need to renew your passport.

It is important to note that you might be permitted to enter Pakistan with your passport if you are a dual national or have another nationality, but it is important to confirm the visa requirements in advance. To prevent any last-minute issues, make sure your travel documents are in order well in advance of the dates you intend to travel.