I don't think that was always 'intended' from the start that the character was meant to be gay, but I watched the show a lot as a kid (and would even sometimes catch it when I was older when there was nothing else on) and the vibe I got from Mr. Ratburn was that he was kind of...ambiguously gay.
Like a lot of his personality could be read as him being gay but it was never outright said that he was (nor does it necessarily mean that he was intended to be gay from his debut and they just kept it as subtext).
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"For God so loved the world that he gave his only Son, so that everyone who believes in him may not perish but may have eternal life." - John 3:16 (NRSVUE)
Remember that it is never too late to accept God's love into your heart and to believe the truth that Jesus Christ died for your sins, was buried, and rose from the dead after three days. Christ's sacrifice was unconditional and it is never too late to invite Him into your heart as your personal Savior!