Is it good for the market? Probably, but then again they are just giving false hope, specially for beginners and it will not be positive experience for them if the market suddenly crashes this year or the prediction didn't get to $20k at the end of the year.
Even beginners must need to search and find themselves on what had happened on bitcoin markets in the past so that they will not be disappointed on unexpected events on this crypto space. An investor must need to be ready to face anything while risking their money as no one could speculate exact things still we need speculations to make ourselves ready for planning for future levels.
Just in the first place, these forecasts have a definite purpose in order to speculate in the cryptocurrency market and perform certain manipulations.
Speculations are not new just because of cryptos. For every markets, there should be some soothsayers and market do react/ignore them on it own way. Spreading speculations and then manipulating markets with the expectation of trapping small investors must be part of every markets and protecting themselves against such manipulation is purely within individual's responsibilities as nothing could be done in the decentralized space.