How can Bog Child relate to the present day?

Two possible ways that Bog Child connects with contemporary issues in Ireland are through considerations of the distant past with present-day politics as well as the country's future. The novel brings those themes together in ways that were timely in the 1980s, but Irish people are confronted with similar issues thirty years later.
Additional discoveries of bodies in peat bogs have been made over the last few decades. Research into the context of the burials and the lives of the people buried, including DNA-based investigations, is an ongoing project. Much of the research is being conducted through the National Museum of Ireland.
The future political and economic status of Ireland, including border issues, has been very much in the news in 2019. The United Kingdom's Brexit initiative has placed the Republic of Ireland in a unique position because it will remain in the European Union if the UK manages to pull out. That would make the Ireland-UK border the only remaining land border between the EU and UK. The situation is often called the "Brexit backstop."
https://www.irishtimes.com/news/politics/brexit-explained-why-does-the-border-matter-and-what-is-the-backstop-1.3661518

https://www.museum.ie/Archaeology/Exhibitions/Current-Exhibitions/Kingship-and-Sacrifice/Bog-Bodies-Research-Project