Power Query usually is that prestep where u filter and transform data beforehand so that the dashboard itself is quick even tho it takes a while to load the data.
You could try loading it with Python code and using pandas to filter out the csv.
Would look something like this:
import pandas as pd
df = pd.read_csv ('file_name.csv')
df= df[df['YEAR'] == 2020]
For more info
pandas df docs