I like to think of 5e as an open platform for lots of RPGs, including D&D 2014, D&D 2024, Tales of the Valiant, A5e, Esper Genesis, Broken Weave, and others so, from that perspective, Tales of the Valiant is 5e. But I presume you're comparing it to either D&D 2014 or D&D 2024.
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