Somebody may want to inform Futaba, JR, Spektrum, etc., etc., etc. about that because every TX I own, and almost every one I have ever owned, has screw on connectors. Hogwash. No truth to that statement whatsoever.
As a matter of fact, as far as I know, DJI is the only major (now) manufacturer that makes such crap.
I love it when blow-hards get on chat forums and make such declaratory statements when they know little to nothing of what they speak.
You must keep up with the times and not stay rooted in the past. It is apparent you are not familiar with FCC Part-15 requirements.
To make it easier for you I have clipped Section 15.203:
Antenna Requirement
"Changing the antenna on a transmitter can significantly increase, or decrease, the
strength of the signal that is ultimately transmitted. Except for cable locating
equipment, the standards in Part 15 are not based solely on output power but also take
into account the antenna characteristics. Thus, a low power transmitter that complies
with the technical standards in Part 15 with a particular antenna attached can exceed
the Part 15 standards if a different antenna is attached. Should this happen it could
pose a serious interference problem to authorized radio communications such as
emergency, broadcast and air-traffic control communications.
In order to prevent such interference problems, each Part 15 transmitter must be
designed to ensure that no type of antenna can be used with it other than the one used
to demonstrate compliance with the technical standards.
This means that Part 15
transmitters must have permanently attached antennas, or detachable antennas with
unique connectors. A "unique connector" is one that is not of a standard type found in
electronic supply stores.
It is recognized that suppliers of Part 15 transmitters often want their customers to be
able to replace an antenna if it should break. With this in mind, Part 15 allows
transmitters to be designed so that the user can replace a broken antenna. When this
is done, the replacement antenna must be electrically identical to the antenna that was
used to obtain FCC authorization for the transmitter. The replacement antenna also
must include the unique connector described above to ensure it is used with the proper
transmitter.
"
Now go take a second look at the offerings of other manufacturers granted FCC Part-15 Type Acceptance for their equipment and come back here and tell us what you have found.