The rubber was actually functional in the old days to protect the upper fork sliders from rocks, mud and debris from nicking the surface, work their way past the upper fork seals and contaminate the fork oil.
Modern metallurgy has improved, seal materials are better, but the boots still offer protection and contribute to the all black "nostalgic" old school "road scrambler" look.
If you remove them, road debris can nick the black finish and may make you wish you did not remove them...I would not remove them yet, give 'em time, they may "grow" on you; just don't be too hasty before you remove them (by all means properly remove the fork sliders) from the triple tree/bike so you do not cut them in case you want to put 'em back later. :newsmile071: