SpaceX are still building Falcon boosters at a higher rate than Ariane are building Ariane stacks, despite reuse. Not to mention a lot more upper stages. Consider the following production figures:

Granted, Ariane 5 is heading towards retirement so they're winding production down, but historically it averaged about 6 per year during the 2010s, which is comparable to the rate SpaceX have built Falcon boosters at since reuse started becoming common practice circa 2018, and they show no signs of slowing given they built 7 last year and 3 in just the first two months of this year.

(Note: I'm using maiden launches as a proxy for production figures. Actual completion dates are likely some months earlier, but over a time period of 5+ years it averages out)

 

Reuse doesn't necessarily have to reduce the number of rockets you have to build, that's stinkin thinkin.

It can instead allow you to build the same number of rockets but get a lot more launches done with those rockets - as evidenced by the Upper Stage figures for Falcon, which are 1:1 with the number of launches in a given year.

Consider also that SpaceX want to build Starship at a rate of one per month despite it being fully reusable.