Timely intraday data?

Am I doing something wrong to get live intraday 15 minute bars? The quotes don’t seem to be near real-time.

Same analysis against smaller sample (350,000 data points) of Polygon data ($200/month) yielded up-to-the-5-minute quotes.

Using my funded credentials, not paper credentials, I looked at the current time versus the recorded time every fifteen minutes for 800 tickers from NYSE, NASDAQ, AMEX and ARCA. No OTC.
849,871 data points from late December, ~two days.
The median time from each snapshot to the latest recorded “bars” data was 19.35 !!hours!!, while the average was much longer. Did not see that coming.
Endpoint: https://data.alpaca.markets/v1/bars/15Min?symbols=