Pine tree troubles
The wooly mass of insects are called pine bark adelgid which are sucking insects. It is fairly common on white pine bark and usually not serious. These insects can be treated using horticultural oils or insecticidal soaps. See the following article from MSU Extension Educator Jill O'Donnell https://www.canr.msu.edu/news/pine_bark_adelgid_becoming_active_in_white_pines
The tree with the cracked bark may have had boresr but often pine borers are secondary insects coming in when a tree is already weakened which can be from a variety of problems including environmental issues, especially periods of drought that have occurred in last three summers. Cannot tell why this tree declined for sure from this picture.