You did not say if it ever gave higher pressure or is this something new. Being new to the house you donít have a history of performance to work with.
From your research you have determined that your well is not pumping dry.
What kind of pipe do you have from the pump to the tank? Thinking of a possible restriction.
Have you pulled to pump to check the inlet screens? Again a possible restriction.
What is the HP and age of the pump?
The tech may be correct in that the time for a replacement is getting near.
Just a few thoughts.