When LL did "I need Love" it DID hurt his core fan base, mainly because it was NEVER done before and people were distraught from seeing this from the same dude that said he's "BAD" and blew the hip hop nation eyes open with his KROOVE GROOVE cameo performance of "Radio". The same dude that claimed was "hard as hell" on some love soft shyt. LL got CRUCIFIED for several years, even by his own peers and Kool Moe Dee capitalized on it. It took "Mama Said Knock You Out" for him to regain some relevancy.
With all that said, "I Need Love" was a HUGE SINGLE and other record labels wanted to jump on that bandwagon, because hip hop radio back in those days only played at late nights and in some stations not at all, but a love ballad ALWAYS would get play and rotation. So, it was pushed upon Big Daddy Kane to be a sex symbol. But he faced the same problem as LL did which was the hardcore hip hop fans wasn't fukkin' with that shyt at all. Yet, and still him being promoted as a SEX SYMBOL worked! That was the ONLY reason Kane was the biggest artist on Cold Chillin'. But then he OVERDID it fukkin' with Madonna, going on PLAYGIRL which was damn near CAREER SUICIDE and people were disillusioned, "like WTF, Kane"!?
Keep in mind, the blending of hip hop & R&B was still like mixing oil and water together. It wasn't until Puffy & Andre Harrell perfected it to which it became more appealing for true hip hop heads to appreciate. Most notably through Mary J. Blige. Because of that shift, it opened the opportunity FOR LL to thrive in the mid-90's to which should of fell off back in '93 with that "14 Shot to the Dome" bullshyt album. So, he (which I believe Puffy was his manger back then too if not mistaken) fitted back in that R&B tracks because it was now more acceptable.
Meanwhile, Big Daddy Kane was an emcee without a label. After that "Daddy's Home" BS album, he was trying to find a comeback and was supposedly to sign with Death Row, but that folded due to all the shenanigans that we all know all to well.
But, in a nutshell... it all about the hip hop climate. LL Cool J basically had better songs. While Kane OVERDID it with the sex symbol shyt and never could recover from that. The Playgirl shyt still burns.