My inlaws have a similar vintage Bosch. I asked how often they cleaned the filter and got a dumb stare. I cleaned it and it had some goo and broken glass but it was much less than I expected for complete neglect.
You don't need to grind the food with the right flow/pump design. Filter protects the pump/spray arms during wash, use an alternate flow path during pump out to send all the big chunks into the drain (bonus points if they use a water jet to purge the big bits).
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