Crashing on blobs on filament resulting in offset subsequent layers  

Crashing on blobs on filament resulting in offset subsequent layers

I started having a problem with something that looks like blob/ribbon like piece of filament deposited on the print, causing printhead to subsequently crash into it, and then continue printing with an offset. See attached photos for a good example from today.

This started happening very frequently (basically any larger print) with seemingly nothing else changing hardware wise on the printer; I used same filament, same settings, same everything for years (both MK4, and prior to that MK3), and literally never experienced this problem before. I did re-add "input shaper" printer into the slicer, which may or may not coincide with this (approximately correlates, but not 100% sure). I did try to add non "input shaper" printer and using that, as well as setting X and Y axis filtering on the printer to off (either of which apparently should disable input shaper, per various posts in forums), with no improvement. The problem still persists, and it'd seem crash detection still doesn't work on top of that.

FWIW, hardware is MK4, hardened steel 0.6mm nozzle (Prusa Nozzle ObXidian), Prusament PC Carbon Fiber filament. Basic default settings on both the printer and in the slicer (few small adjustments, such as 100% infill), latest profiles from Prusa, latest firmware, etc...

Any help what could be causing this? Why would the problem suddenly start happening. With no crash detection (because of input shaper?), I'm worried eventually this could cause physical damage to the printer. Not to mention all the wasted filament.

Also, how to get crash detection back? If on MK4 the choice is between input shaper and crash detection (but not both), I'd rather have crash detection enabled.