Boot loop when the new screen is in the frame

Is your frame bent? Apple products can act up when cables get pinched. I have seen this model boot loop when the home button is not connected correctly. It’s possible there is pressure being placed on the home button connector when it’s pushed in.

Check the flex cables especially the small one that goes to right side connector, for the home button if this is getting pinched or damaged then it can be disconnecting the home button or causing a problem with that, if the home button gets disconnected it will usually restart the phone, the flex on the screen may be damaged or the big chip at the back of the screen could be putting too much pressure on something or like suggested the phone could be bent and the pressure of the screen could be causing audio ic issues…

Lay the phone flat on desk face down without the screen connected and with the sim card slot side facing u, look for bends.

check if there is any shortcut between the metallic cover and the screen flex cables. should be an adhesive to protect that happen…