It's 2023. Hard drive space shouldn't be an issue. Test installing the full software suite, make it work, and you know the lesser installs will all work.
That US$100k seems to have arrived over the last year, and their overheads - from quickly looking over their OpenCollective expenses tab - seem to be mostly buying hardware for CI things, and a monthly GSuite bill.
It's also pretty likely they get a lot of their resources for free / sponsored too.
Do you really not see any advantage to maintainers having visibility into what packages people actually use?