How should I understand the absence of conjunctions in 流行音乐歌唱的大都是男女爱情、歌词贴近生活、通俗易懂、易于传唱、受到欢迎、不足为怪?
流行音乐歌唱的大都是男女爱情、歌词贴近生活、通俗易懂、易于传唱、受到欢迎、不足为怪。

There are punctuation issues in this sentence. A way to modify it is:

流行音乐歌唱的大都是男女爱情、歌词贴近生活、通俗易懂、易于传唱、受到欢迎不足为怪。

We can also replace 顿号（、） with 逗号（，）：

流行音乐歌唱的大都是男女爱情，歌词贴近生活，通俗易懂，易于传唱，受到欢迎不足为怪。

The sentence should be read as:

[流行音乐] /歌唱的/大都是/男女爱情，歌词贴近生活，通俗易懂，易于传唱，受到欢迎不足为怪。

It's topic + comment structure. The topic is [流行音乐]. The comments: [歌唱的大都是男女爱情], [歌词贴近生活], [通俗易懂], [易于传唱], [受到欢迎不足为怪].
There is no need for conjunctions here. The comments are paralleled by commas. I guess your issue is not conjunction per se, but parsing.(Correct me if I'm wrong.)
For translation, you can separate into a few sentences. @fefe already presented one. You might come out with a better one considering you are an English speaker.
Edit:
This might help you further:


[流行音乐]歌唱的大都是男女爱情;

[流行音乐]歌词贴近生活;

[流行音乐]通俗易懂;

[流行音乐]易于传唱;

[流行音乐]受到欢迎不足为怪。



P. S.  There is a trick in the first part, [流行音乐]歌唱的大都是男女爱情.  It's very easy to parse it as 流行音乐歌/唱的/大都是/男女爱情. So, you would take [流行音乐歌] as the topic.  But actually, the topic should be 流行音乐 and 歌唱 as a whole is a single word to mean sing. It would be more obvious to write [流行音乐][歌唱的内容]大都是男女爱情.  I saw other answers took [流行音乐歌] as the topic as well, so I think it deserves to point it out.