For a planet-scale project that I worked on, a multi-layer PMTiles set generated from GeoJSON by Tippecanoe reduced the amount of storage needed by about 60% vs. MVT, at the cost of a longer build time. Result was a single file served by MapLibre on a static web server, no tileserver needed.
The storage savings allowed us to add 3 additional zoom levels on the same cheap, storage-constrained VPS host that ran the web server. We considered moving it to S3, which would be much easier with PMTiles since it's just a single file, but it would've only cost us more money and we didn't need edge caching.
I'd link to the project but it'd be a waste of time vs. reading the two-step process to generate in the PMTiles docs: https://docs.protomaps.com/pmtiles/create#tippecanoe
And the 4-LOC installation process of the PMTiles library for MapLibre: https://docs.protomaps.com/pmtiles/maplibre
