Since when?
The reports are that Yoro and Ugarte were club-led signings. Zirkzee also has no particular connection to ETH other than being Dutch, nor was it reported anywhere I can see that he was an ETH-led signing.
De Ligt has an obvious connection to ETH, but ETH outright said that the club suggested the signing. Which tracks given all the reports that the club had interest in him when he made his prior moves to Juve and Bayern. We also know we were initially interested in Branthwaite, again with zero indication that was a particularly ETH-led pursuit either.
That leaves Mazraoui, the cheapest of the signings, replacing a player who who was out of contract next summer, and offering an obvious upgrade on him.
It's hardly some massive commitment to ETH personally, unless you start making unfounded assumptions about who "directed" these transfers.
We know ETH has a veto, so targets will all be okayed by him, but that doesn't mean he drove them. And in the case of several of them, it's been directly reported he didn't.