The ST not scoring is a well known problem for a lot of players I had it myself, 0,5 is actually not bad at all. I kinda forgot about it since for around 8 seasons I've had 2 great main ST. But now I'm facing the same problem with my new ST and I think it has to do with the formation.
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In the formation I play with an AMC my ST Mayer scored a lot, he scored 25 goals in 25 matches in one season and 23 in 24 in another one. He combined a lot with my AMC Son giving assists to each other, Son was also a top scorer, my other few goals from this formation usually came from my ML and MR but the 2 players carried the weight.
This season I'm mainly using 4-5V-1 and my new ST is suffering a lot with only 3 goals. Son now plays as an AML and continues to be my main source of goals with my other winger. Also I have had more goals from my MC's and even the defenders sometimes. I think ST's perform better when they have an AMC or another ST beside them.
The game suggests that playing through the middle helps them and I find that true in my experience, but you also need to have some players there like I mentioned.