"LE Secure Connections" when there is no IO capability

I want to realize "LE Security Mode 1: Level 4".
However, there is no IO capability in both devices.

I tried the following.
1) Set the IO capability of both devices to "BLE_GAP_IO_CAPS_DISPLAY_YESNO".
2) With this setting, the authentication operation is performed with "Numeric Comparison".
3) Reply "YES" unconditionally on both devices. (No operation by the user)

In the above case, "auth_status.sm1_levels.lv4 = 1" was obtained at the "BLE_GAP_EVT_AUTH_STATUS" event.
However, since there is no IO capability, there is no operation from the user.
Even in that case, is it OK to think that "LE Security Mode 1: Level 4" was realized?
Also, are there any security concerns about the lack of user interaction?

Thanking you in advance.