Unlike his public assessment, he was relatively highly evaluated as a Sengoku daimyo, but recent studies regard Yoshimoto's frequent military actions driven by aggressive territory expansion as the cause of fatigue in his vassals and the people of the domain, and it is has been determined that this was one of the causes leading to such a rapid decline of the Imagawa clan after his death.
このように一般の評価と違い戦国大名として高い評価を受けていた面もあるが、近年では積極的な領土拡大を理由とした度重なる軍事行動が、家臣や領民の疲弊を招き、死後の今川氏が急速に衰退した原因の一つであるとも指摘されている。