Rwanda's spend on Rwandair and its advertising itself to tourists on English football jerseys is a good investment. Tourism has doubled in ten years and spend has tripled. Since Rwanda is positioning itself as a financial services hub (exports of goods from landlocked countries have serious limitations, much more so in Central Africa), the ability for easy access is essential, one that will be helped by an airline. Given the poor standards of airlines in the region, and Rwanda's relatively high standards in everything as compared to those of other countries in the region, Rwandair is easily competitive.
More specifically, the country's reputation for efficiency and its location has attracted Qatar as a partner in the new, modern Bugesera Airport that is under construction. It seems that its investments are producing results, including consistently strong economic growth. The source is cited below.
"Growth averaged 7.2% a year over the decade to 2019, while per capita gross domestic product (GDP) grew at 5%."
https://www.worldbank.org/en/country/rwanda/overview