The Qing Dynasty perished. What made the northern warlords support the Qing Dynasty so stubbornly?

Judging from the dynasties, when the emperor perished, he was either killed, anonymous or controlled. The demise of the Qing dynasty ended when the Qing court announced its abdication, but the emperor and royal family of the Qing dynasty did not die out and were still enshrined by the Beiyang government. The existence of Puyi made many people want to restore the Qing Dynasty, and they would support him as emperor.

If successful, these warlords will be the founding fathers, and their reputation will be praised by future generations. Many warlords had an imperial dream for their own interests and loyalty to the Qing Dynasty. It can be seen that by making good use of the conditions at that time, they still had a chance to restore the Qing Dynasty, and their disunity eventually lost the opportunity. However, the harmonious system is the general trend, and the implementation of the imperial system will only go backwards in history and will not revitalize China.