Set Instant Pot to Sauté mode on high. Once Instant Pot has preheated, add sliced bacon and chopped onion to pot. Cook, stirring occasionally, until bacon begins to crisp and onion has softened, approximately 12 minutes.
Add garlic cloves to sautéed bacon and onions. Stir well and cook just until garlic is fragrant, approximately 30 to 60 seconds.
Add collard greens and chicken broth to Instant Pot. Continue in Sauté mode while stirring and scraping up any browned pieces of bacon or onion that may be stuck to bottom of Instant Pot. Cook just until greens begin to wilt, approximately 2 minutes.
Add salt, pepper, apple cider vinegar, and hot sauce to Instant Pot. Stir to incorporate, then cancel Sauté mode and cover pressure cooker with lid.
Lock lid on Instant Pot and set valve to Sealing position. Set Instant Pot to Manual High Pressure with 12-minute cook time. Instant Pot will come to pressure (5 to 10 minutes) and then 12-minute cook time will begin.
When 12-minute cook time is up, carefully Quick Release pressure. Once steam has fully escaped, carefully remove lid from Instant Pot and set aside. Divide greens into portions and serve warm with additional hot sauce if desired.