The marketing of 5G networking is more than a bit confusing because we're not talking about one offering, we're talking three: millimeter, mid-band, and low-band. Millimeter-wave uses very high frequencies, above 24GHz, and that's the one that needs lots of short-range boxes installed and will be mostly for outdoor purposes. Mid-band uses frequencies in the 2.4 GHz to 4.2 GHz range and is the one that your smartphone, when compatible, will get a real nice speed increase. Low-band won't deliver any discernable speed benefits but should perform better inside buildings due to its use of lower frequencies.
So the first question to ask when someone spouts on 5G is "which one are you talking about?".