Pinned straw:
To echo what @Wini and @Randy have said - explaining the expanding cost base appeared to have been a key priority during the report presentation. I think management did a good job in their communications.
One example is how Managed Trading Services (MTS) is now contributing to $3m in ARR.
A rough timeline, to highlight how quickly this came about:
They've had to invest in systems and people but now have an expanded product offering which has seen commercial success very quickly, and is a key driver of the group's growth.
There's good costs and bad costs. And so far it appears to be good costs. As others have mentioned, the CFO has flagged that the growth in costs have peaked.
CFO on the public conference call regarding costs: "we think that will moderate in the back half of FY26 and the growth rate should slow significantly going forward in future periods."
Good summary @JohnnyM. The spiralling share price into the results had me fearing the worst, but all things considered I think this is a pretty good result from RTH. Organic revenue growth was about 17%, plus a full period of the recent Asia acquisition (though they clarified a 40/60 revenue split mirroring Hong Kong racing season):

You are right they have spent for this growth and at face value you could criticise management and view the lagging profitability as a negative. But I thought they handled it very well in the presentation subsequent earnings call.
They gave far more detail than they have in the past where they have spent money, the products they have built with it and the early returns it has provided. There were inevitably some questions on the pace of expense growth moving forward and the CFO said the "bulk" of investments are behind them. I think it's easy to see the truth in that, they have hired out the Managed Trading team and RAS Asia execs, and I can see incremental revenue falling pretty cleanly from here.