That's bollocks. An eSIM module is exactly the same chip as in a normal SIM card - right down to the electric specifications and communication protocols, so you can hook up a provisioned eSIM module to a phone or a SIM card to a device using an eSIM chip and it will Just Work (tm).
The only difference is that the eSIM module is allowing the baseband chip to flash a new set of cryptographic keys, a process that will (usually) require the cooperation of the main SoC to get and transmit said keys.
The only scenarios where an attacker could reprogram your SIM remotely is either a malicious actor in the provider network (at which point there is the question why an attacker would want to reprogram your SIM at that point, given all they can do is give your SIM card access keys to another network) or a malicious actor with an IMSI catcher.
In both scenarios the attacker would require an exploit in your specific baseband and the correct cryptographic keys (or yet another exploit) for the eSIM to accept the new profile... and at the degree of knowledge, hardware and the actual exploits required to get to the point a successful attack requires, your attacker will be a government or an NSO-scale enterprise. And seriously, at that point you already have lost anyway because they have exploits for the OS you're running on whatever device you use, they don't need to deal with taking over your SIM card.