The site says

"Das Vorhandensein von datenschutzfreundlicheren Optionen steht im Widerspruch zu einem berechtigten Interesse"

which means

"The existence of more privacy-friendly options contradicts a legitimate interest."

But did they really test if the alternatives block bots as well as reCaptcha?

If not, wouldn't that mean there is a legitimate interest in using reCaptcha?

If the mere existence of more privacy-friendly options, no matter how inferior, means you cannot use a certain service, wouldn't that make the use of pretty much every service illegal in the EU?