From my limited experience with PoE switches, how much power being drawn in relation to how much the switch can supply has a notable impact on efficiency. Specifically, when only one or two ports on a 48-port switch are delivering PoE, the increased AC power drawn from the wall is disproportionately high. Hence, any setup where you’re using more of the PoE switch’s potential power tends to increase overall efficiency.
My guess is that it has to do with efficiency curves that are only reasonable when heavily loaded for enterprise customers. In any case, if either of those two candidate switches meet your needs today and with some breathing room, both should be fine. I would tend to lean towards Netgear before TP-Link though, out of personal preference.
A Nintendo Wii would also work, as exemplified by this blog running on a NetBSD Wii.
But in all seriousness, the original comment has a point: using a mobile phone as a server is possible but also wastes a lot of the included hardware, like the cellular baseband, the touchscreen, and the voice and Bluetooth capabilities. Selling the phones and using the proceeds to purchase a used NUC or an SFF PC would give you more avenues to expand, in addition to just being plain easier to set up, since it would have USB ports, to name a few luxuries.