The phrase "almost exclusively devoted" is correct and usable in written English.
It can be used to describe a strong focus or commitment to a particular subject, activity, or cause, while acknowledging that there may be minor exceptions.
Example: "She is almost exclusively devoted to her research, spending most of her time in the lab."
Alternatives: "primarily dedicated" or "largely committed".
Our days are almost exclusively devoted to kayaking.
Suppiluliumas' military career was almost exclusively devoted to struggles with the kingdom of Mitanni in the east and the reestablishment of a firm Hittite foothold in Syria.
In Turkey, news coverage was almost exclusively devoted to troubled negotiations over the European Union and the issue of Kurdish separatists.
But it is interesting to recall that it actually constituted an innovation for the theater company, then called the New York Shakespeare Festival and almost exclusively devoted to work by the playwright of its name.
The violinist Leila Josefowicz, her career almost exclusively devoted to new music, includes Schumann's Sonata No. 1 in A Minor for Violin and Piano, as well as works by Falla and Messiaen, in a recital that highlights more recent music by John Adams and Erkki-Sven Tüür (Nov. 10).
Although the latest Times Square signs are almost exclusively devoted to their sponsors, the owners recognize the commercial potential of giant video and digital displays that can be changed far more easily and rapidly than neon spectaculars, painted walls or even vinyl sheets.
Article 46, exclusively devoted to child rights, has been voted for inclusion almost unanimously (171 for, 1 against, 2 abstentions).
There, large mechanized holdings are devoted almost exclusively to corn (maize) cultivation.
Court TV, a network devoted almost exclusively to live coverage of trials, was flourishing.
Loosening many of the earlier restrictions has also rejuvenated many art forms previously devoted almost exclusively to propaganda.
But it's no joke that on the East End where I live, an area once devoted almost exclusively to agricultural production is being overrun with subdivisions.
