"We do not teach new things when it comes to our core beliefs", DOT, thats the problem of following men instead of the Christ.
Watchtower "core beliefs" is in direct conflict with the christian writings such as:
-an earthly resurection (it contradicts both Jesus statement and Pauls teaching)
-Christians seperated into two groups(earthly, heavenly class) it contradicts Jesus own statement that his followers were to be ONE herd under ONE sheperd, Jesus himself.
-a "Governing Body" operated in the 1´st century, in direct conflict with the apostolic letters. See
https://anointedjw.org/Governing_Body_Myth.html
-only 144,000 literal will ever go/enter the heavenly Kingdom, the very message that Jesus himself introduced to ALL his followers, not just a few.
“So Jesus said to them: ‘Most truly I say to you, unless you eat the flesh of the Son of man and drink his blood, you have no life in yourselves. Whoever feeds on my flesh and drinks my blood has everlasting life, and I will resurrect him on the last day; for my flesh is true food and my blood is true drink. Whoever feeds on my flesh and drinks my blood remains in union with me, and I in union with him.” – John 6:53-56
"Notice that this is not a prophecy. This is a plain and open teaching that is very clear and to the point. Unless we eat and drink of the Christ, we have no life or sharing with him! Yet, the Governing Body actually teaches that one can refuse to eat and drink of the Christ, and still live forever on the earth – as if Jesus does not have authority over the earth! They take great pains to explain their convoluted theories about everlasting life on earth, which is a theory Jesus never taught". (Quote from www.AnointedJW.org/ A memorial of offense.
D.O.T, if you do not start to partake at the memorial you will not gain life. Pure and simple. The "Paradise Earth forever" is a fallacy and a very dangerous one to.