Why FPS (frames per second) dropped after I added a 30ms delay between frames sending to client using RTC in python?

Question

I modified the below code to the code just below it to send frames after 30ms delay to get better FPS but to my surprise they dropped drastically instead of going up, earlier I was receiving 22 fps after modification I got just 2 fps

Before:

def _producer(self):
    old_frame = None
    self._setReady(True)
    while not self._shouldClose:
        if not context.context_dict[context.rtc_connections]:
            time.sleep(0.1)
            continue
        frame_to_send = context.context_dict[context.currentFrame]
        if old_frame is None:
            self._put_nowait(frame_to_send)
        else:
            is_similar = old_frame == frame_to_send
            if isinstance(is_similar, np.ndarray):
                is_similar = is_similar.all()

            if not is_similar:
                self._put_nowait(frame_to_send)

        if frame_to_send is not None:
            old_frame = frame_to_send

    self._setReady(False)
    self._log.info("Ended camera capture")

After:

def _producer(self):
    self._setReady(True)
    last_frame_time = None

    while not self._shouldClose:
        if not context.context_dict[context.rtc_connections]:
            time.sleep(0.1)
            continue

        if last_frame_time is None:
            last_frame_time = time.time()
            frame_to_send = context.context_dict[context.currentFrame]
            self._put_nowait(frame_to_send)

        current_frame_time = time.time()

        if round(current_frame_time - last_frame_time, 2) < 0.03:
            continue

        last_frame_time = current_frame_time

        frame_to_send = context.context_dict[context.currentFrame]

        if frame_to_send is not None:
            self._put_nowait(frame_to_send)

    self._setReady(False)
    self._log.info("Ended camera capture")