If this is the last Abrams era film, will I be disappointed? Yes. Can I live with it? Yes. Trek as a brand is very unlikely to die. Someone else may get a crack at it, in ten years, fifteen years,etc. Maybe even sooner. Reboots come along much more quickly these days than they used to.
I was disappointed that Timothy Dalton only got two movies as Bond (one of my favourite Bonds), but his 2 are still IMO two of the best in the franchise. Audiences weren't ready for a darker take on the character at that time. At least we got two films of his.
I kind of have the same philosophy about Abrams Trek. I can live with it if this is the last we see of it. The next person to head the franchise, should this film not get a sequel, will probably reboot again