Piracy is copyright infringement, not theft, so laws related to theft don't apply. Copyright offences do not have the same tradition of separate 'petty' and 'grand' offences based on the value of the subject matter.
In Australia, copyright offences exist under Commonwealth law. Commonwealth law does not recognise a misdemeanour/felony distinction. Instead, there is a summary/indictable distinction. This distinction is particularly relevant in respect to the guarantee under section 80 of the Australian Constitution of a jury trial for offences tried on indictment (although Parliament can apply any punishment it likes for summary offences and prosecutors can proceed summarily even on indictable offences).
In Commonwealth law, indictable offences are those which can be punished with a maximum sentence of greater than 12 months: Crimes Act 1914 (Cth) s 4G.
Commonwealth copyright offences have indictable and summary forms, e.g. 'commercial-scale infringement prejudicing copyright owner' under the Copyright Act 1968 (Cth) s 132AC(1) and (2) respectively. The summary form is punishable by two years' imprisonment, explicitly overriding the rule in s 4G of the Crimes Act. The difference between the two forms of this offence, as an example, is not related to the size of the infringement but instead turns on the defendant's knowledge of the circumstances that (1) the infringements prejudice the copyright holder and (2) the infringements are on a commercial scale; for the indictable offence the defendant must be reckless as to these circumstances but for the summary offence the defendant need only be negligent.
Another copyright offence is 'make or possess a device for making an infringing copy' under section 132AL of the Copyright Act. Again this offence has both summary and indictable forms, differing in respect to the defendant's mental state. You might commit the indictable form of this offence if you knowingly possess the technical means to pirate the Train Simulator DLC and decide to do so.
So, in answer to your question, yes it could be an indictable offence (the closest thing to a felony we have under the relevant law in Australia).