If someone is in EU and is affected by this they could potentially utilize GDPR to make both Microsoft and LG take responsibility for this.

It's hard to say directly from the article if there is any GDPR breach. If everything was part of the installer and it doesn't actually submit anything (including downloading the ad) to LG then it's harder to argue that there is GDPR violation, but knowing the SOP of these kinds of software that is unlikely.

If the software did indeed send personal data to LG then there are at least following question: How was Article 13 notice delivered to user? Article says that this was installed quietly. Did Microsoft deliver Article 13 compliant notice to user at some point? They probably did deliver their own notice (though it's open question if it's compliant), but not LG's. However since Microsoft is the one that installed the software and they exercise control over the standards which must be met, it's possible that they would end up being joint controller at least for some processing.

I should add that Article 13 requires that the notice is given "at the time when personal data are obtained". The only exception is when "data subject already has the information" and possible Article 23 restrictions, but those are unlikely to apply.

If someone wants to make a complaint they should first make Article 15 request to LG. Copy of personal data is useful, but 15(1) information is the primary goal. Additionally ask for information on how and when did LG provide you the Article 13 notice if they did indeed process your personal data.

After that if they cannot show that they provided Article 13 notice when they received your personal data submit a complaint to your local DPA. You can additionally flag other violations as well if they are applicable (e.g. not naming recipients as part of Article 15 response, not giving actual retention time or meaningful information how that is determined, invalid legal basis etc.). You should also flag in the complaint that Microsoft is likely joint controller for some of the processing given that they are the ones who approved the automatic install of the software which violated GDPR.