Are those Muslims who do not offer their daily prayers, still considered to be in the fold of Islam?

A majority of scholars hold that he still remains a Muslim, but a minority holds that if his abandonment of prayer is deliberate, then that is enough to take him out of Islam, because the Prophet (ﷺ) said: “The covenant that distinguishes between us and them is the prayer, and whoever neglects it has disbelieved.” [1]

The majority of scholars interpreted this to mean that he becomes a disbeliever in actions. The Prophet (ﷺ) said: “Whoever goes to a fortuneteller and believes what he says, has disbelieved in that which was revealed to Muhammad (peace and blessings of Allah be upon him).”  [2]

So, if you pick up a magazine and read the horoscope which is easily accessible to all of us, that is the act that disbelievers do, and if a person does it, it doesn't mean that he becomes a disbeliever until he accepts whatever is in the horoscope.

And Allah knows best.

References:

[1] At-Tirmidhi, Hadith: 2621; An-Nasa'I, Hadith: 464, Ahmad 5: 346, 35

[2] Abu Dawood (3904), al-Tirmidhi (3904) and Ibn Majaah (936); classed as saheeh by al-Albaani in Saheeh Ibn Maajah