QGIS on many platforms for the fact that - its 1 CPU-bound, does not facilitate Spatial SQL and does not partition data when loading so-called attribute tables. Literally not useful for layers with more than 500k features. Already addressed many times in their issues on github, the short answer is - it will take ages to rewrite it.
It is perhaps too much to say, but QGIS is a dead-end for GIS systems in its current form. Russians branched 2.x into something called NextGIS btw.
It is perhaps too much to say, but QGIS is a dead-end for GIS systems in its current form. Russians branched 2.x into something called NextGIS btw.